diff --git a/doc/agent-smoke-cases.md b/doc/agent-smoke-cases.md
index 3363f63..7d90fb5 100644
--- a/doc/agent-smoke-cases.md
+++ b/doc/agent-smoke-cases.md
@@ -75,7 +75,8 @@ bash scripts/agent-smoke.sh --cdp-port 9222 --cases AGENT-CHROME-001,AGENT-CHROM
 1. `上一帖` 按钮存在
 2. `下一帖` 按钮存在
 3. `选项` 按钮存在
-4. `新标签打开` 链接存在
+4. `回复主题` 按钮存在
+5. `新标签打开` 链接存在
 
 ### AGENT-CHROME-003：设置面板打开和关闭
 
@@ -266,6 +267,49 @@ bash scripts/agent-smoke.sh --cdp-port 9222 --cases AGENT-CHROME-001,AGENT-CHROM
 2. 抽屉保持打开
 3. `location.href` 仍然停留在列表页
 
+### AGENT-CHROME-014：主题回复入口与悬浮开关
+
+范围：
+头部 `回复主题` 主入口 + 可选悬浮快捷入口
+
+状态：
+当前不在默认批量脚本中
+
+步骤：
+
+1. 打开任一主题抽屉
+2. 确认头部工具栏存在 `回复主题`
+3. 读取右侧 `.ld-drawer-reply-fab` 的可见性
+4. 在 `选项` 中把 `悬浮回复入口` 切到 `开启`
+5. 点击头部 `回复主题` 或右侧悬浮按钮
+
+断言：
+
+1. 默认仅显示头部 `回复主题`，右侧悬浮按钮默认隐藏
+2. 切到 `开启` 后，右侧悬浮按钮变为可见
+3. 设置层打开时，右侧悬浮按钮不应继续透出或可点击
+4. 点击任一主题级回复入口后，`#ld-drawer-reply-panel` 打开
+5. 回复面板标题默认是 `回复主题`
+
+### AGENT-CHROME-015：头部工具栏按钮不应挤成竖排
+
+范围：
+抽屉头部工具栏布局回归
+
+状态：
+当前不在默认批量脚本中
+
+步骤：
+
+1. 打开任一主题抽屉
+2. 读取 `.ld-drawer-actions` 中可见按钮和链接的布局信息
+
+断言：
+
+1. 头部工具栏可见操作项不少于 5 个
+2. 文本按钮和链接都保持 `white-space: nowrap`
+3. 可见文本按钮的宽度应明显大于高度，避免被挤成竖排窄条
+
 ## 3. 记录格式
 
 执行完用例后，建议按下面格式留证据：
diff --git a/scripts/agent-smoke.sh b/scripts/agent-smoke.sh
index 6d48287..441aae2 100755
--- a/scripts/agent-smoke.sh
+++ b/scripts/agent-smoke.sh
@@ -16,6 +16,13 @@ DEFAULT_CASES=(
   "AGENT-CHROME-010"
 )
 
+ALL_CASES=(
+  "${DEFAULT_CASES[@]}"
+  "AGENT-CHROME-013"
+  "AGENT-CHROME-014"
+  "AGENT-CHROME-015"
+)
+
 CASES=("${DEFAULT_CASES[@]}")
 PASS_COUNT=0
 FAIL_COUNT=0
@@ -34,7 +41,7 @@ EOF
 }
 
 list_cases() {
-  printf '%s\n' "${DEFAULT_CASES[@]}"
+  printf '%s\n' "${ALL_CASES[@]}"
 }
 
 while [ "$#" -gt 0 ]; do
@@ -137,6 +144,7 @@ drawer_state() {
   const root = document.getElementById("ld-drawer-root");
   const settingsButton = root?.querySelector(".ld-drawer-settings-toggle");
   const settingsPanel = root?.querySelector("#ld-drawer-settings");
+  const replyButton = root?.querySelector(".ld-drawer-reply-toggle");
   const link = root?.querySelector(".ld-drawer-link");
   return {
     pageUrl: location.href,
@@ -148,6 +156,8 @@ drawer_state() {
     settingsText: settingsButton?.textContent?.trim() || null,
     settingsExpanded: settingsButton?.getAttribute("aria-expanded") || null,
     settingsHidden: settingsPanel?.hasAttribute("hidden") ?? null,
+    replyText: replyButton?.textContent?.trim() || null,
+    replyHidden: replyButton?.hidden ?? null,
     newTabText: link?.textContent?.trim() || null,
     newTabHref: link?.getAttribute("href") || null,
     newTabTarget: link?.getAttribute("target") || null,
@@ -543,6 +553,139 @@ EOF
   ab_eval "$script"
 }
 
+reply_entry_state() {
+  local script
+  script=$(cat <<'EOF'
+(() => {
+  const root = document.getElementById("ld-drawer-root");
+  const headerButton = root?.querySelector(".ld-drawer-reply-toggle");
+  const fabButton = root?.querySelector(".ld-drawer-reply-fab");
+  const panel = root?.querySelector("#ld-drawer-reply-panel");
+  const fabRect = fabButton?.getBoundingClientRect?.() || null;
+  const fabStyle = fabButton ? getComputedStyle(fabButton) : null;
+  return {
+    headerExists: headerButton instanceof HTMLButtonElement,
+    headerText: headerButton?.textContent?.trim() || null,
+    headerHidden: headerButton?.hidden ?? null,
+    headerExpanded: headerButton?.getAttribute("aria-expanded") || null,
+    fabExists: fabButton instanceof HTMLButtonElement,
+    fabText: fabButton?.textContent?.trim() || null,
+    fabHidden: fabButton?.hidden ?? null,
+    fabDisplay: fabStyle?.display || null,
+    fabRendered: Boolean(fabRect && fabRect.width > 0 && fabRect.height > 0),
+    fabExpanded: fabButton?.getAttribute("aria-expanded") || null,
+    panelHidden: panel?.hasAttribute("hidden") ?? null,
+    panelTitle: panel?.querySelector(".ld-reply-panel-title")?.textContent?.trim() || null
+  };
+})()
+EOF
+)
+  ab_eval "$script"
+}
+
+toolbar_layout_state() {
+  local script
+  script=$(cat <<'EOF'
+(() => {
+  const toolbar = document.querySelector("#ld-drawer-root .ld-drawer-toolbar");
+  const actions = document.querySelector("#ld-drawer-root .ld-drawer-actions");
+  const items = Array.from(actions?.querySelectorAll("button, a") || [])
+    .filter((node) => !node.hidden)
+    .map((node) => {
+      const rect = node.getBoundingClientRect();
+      const style = getComputedStyle(node);
+      const text = (node.textContent || "").replace(/\s+/g, " ").trim();
+      return {
+        text,
+        width: Math.round(rect.width),
+        height: Math.round(rect.height),
+        whiteSpace: style.whiteSpace,
+        display: style.display
+      };
+    });
+
+  const toolbarStyle = toolbar ? getComputedStyle(toolbar) : null;
+  const visibleTextItems = items.filter((item) => item.text);
+
+  return {
+    toolbarExists: Boolean(toolbar),
+    actionsExists: Boolean(actions),
+    gridTemplateColumns: toolbarStyle?.gridTemplateColumns || null,
+    visibleCount: items.length,
+    items,
+    nowrapOk: visibleTextItems.every((item) => item.whiteSpace === "nowrap"),
+    widthOk: visibleTextItems.every((item) => item.width >= 44 && item.width > item.height)
+  };
+})()
+EOF
+)
+  ab_eval "$script"
+}
+
+click_reply_trigger() {
+  local target=$1
+  local selector_json script
+  case "$target" in
+    header)
+      selector_json='"#ld-drawer-root .ld-drawer-reply-toggle"'
+      ;;
+    fab)
+      selector_json='"#ld-drawer-root .ld-drawer-reply-fab"'
+      ;;
+    *)
+      echo "{\"ok\":false,\"reason\":\"unknown-target\",\"target\":\"$target\"}"
+      return 0
+      ;;
+  esac
+
+  script=$(cat <<EOF
+(() => {
+  const target = $(printf '%s' "$target" | jq -Rs .);
+  const button = document.querySelector($selector_json);
+  if (!(button instanceof HTMLButtonElement)) {
+    return { ok: false, reason: "reply-trigger-not-found", target };
+  }
+
+  button.click();
+  return {
+    ok: true,
+    target,
+    hidden: button.hidden,
+    expanded: button.getAttribute("aria-expanded") || null,
+    text: button.textContent?.trim() || null
+  };
+})()
+EOF
+)
+  ab_eval "$script"
+}
+
+close_reply_panel_if_open() {
+  local script
+  script=$(cat <<'EOF'
+(() => {
+  const panel = document.querySelector("#ld-drawer-root #ld-drawer-reply-panel");
+  if (!(panel instanceof HTMLElement)) {
+    return { ok: false, reason: "reply-panel-not-found" };
+  }
+
+  if (panel.hasAttribute("hidden")) {
+    return { ok: true, closed: false };
+  }
+
+  const button = panel.querySelector(".ld-reply-panel-close");
+  if (!(button instanceof HTMLButtonElement)) {
+    return { ok: false, reason: "reply-panel-close-not-found" };
+  }
+
+  button.click();
+  return { ok: true, closed: true };
+})()
+EOF
+)
+  ab_eval "$script"
+}
+
 click_refresh_button() {
   local script
   script=$(cat <<'EOF'
@@ -601,6 +744,8 @@ run_002() {
   if [ "$(echo "$state" | jq -r '.prevText // empty')" = "上一帖" ] \
     && [ "$(echo "$state" | jq -r '.nextText // empty')" = "下一帖" ] \
     && [ "$(echo "$state" | jq -r '.settingsText // empty')" = "选项" ] \
+    && [ "$(echo "$state" | jq -r '.replyText // empty')" = "回复主题" ] \
+    && [ "$(echo "$state" | jq -r '.replyHidden')" = "false" ] \
     && [ "$(echo "$state" | jq -r '.newTabText // empty')" = "新标签打开" ]; then
     record_pass "$case_id" "toolbar ready"
   else
@@ -802,7 +947,12 @@ run_010() {
     return 0
   }
 
-  before=$(refresh_button_state)
+  if ! before=$(wait_for_refresh_idle); then
+    restore_settings_subset "$original_settings"
+    record_fail "$case_id" "刷新按钮在切换场景后未进入可点击状态: $(echo "$before" | jq -c '{exists, hidden, disabled, text}')"
+    return 0
+  fi
+
   click=$(click_refresh_button)
   if ! after=$(wait_for_refresh_idle); then
     :
@@ -978,6 +1128,108 @@ run_013() {
   fi
 }
 
+run_014() {
+  local case_id="AGENT-CHROME-014"
+  local original_settings original_floating off_result off_state on_result on_state settings_open_state click_result panel_state
+  local passed=0
+  local detail=""
+
+  open_topic_by_index 0 >/dev/null || {
+    record_fail "$case_id" "无法打开抽屉"
+    return 0
+  }
+
+  original_settings=$(settings_values)
+  original_floating=$(echo "$original_settings" | jq -r '.floatingReplyButton // empty')
+  if [ -z "$original_floating" ]; then
+    record_fail "$case_id" "无法读取悬浮回复入口设置"
+    return 0
+  fi
+
+  off_result=$(set_setting_value floatingReplyButton off)
+  if [ "$(echo "$off_result" | jq -r '.ok')" != "true" ]; then
+    record_fail "$case_id" "无法关闭悬浮回复入口: $off_result"
+    return 0
+  fi
+  ab wait 1200 >/dev/null
+  off_state=$(reply_entry_state)
+
+  on_result=$(set_setting_value floatingReplyButton on)
+  if [ "$(echo "$on_result" | jq -r '.ok')" != "true" ]; then
+    set_setting_value floatingReplyButton "$original_floating" >/dev/null || true
+    record_fail "$case_id" "无法开启悬浮回复入口: $on_result"
+    return 0
+  fi
+  ab wait 1200 >/dev/null
+  on_state=$(reply_entry_state)
+
+  ensure_settings_open
+  settings_open_state=$(reply_entry_state)
+  ensure_settings_closed
+  ab wait 400 >/dev/null
+
+  click_result=$(click_reply_trigger fab)
+  ab wait 800 >/dev/null
+  panel_state=$(reply_entry_state)
+
+  close_reply_panel_if_open >/dev/null || true
+  ab wait 400 >/dev/null
+  set_setting_value floatingReplyButton "$original_floating" >/dev/null || true
+  ab wait 800 >/dev/null
+  ensure_settings_closed
+
+  if [ "$(echo "$off_state" | jq -r '.headerExists')" = "true" ] \
+    && [ "$(echo "$off_state" | jq -r '.headerText // empty')" = "回复主题" ] \
+    && [ "$(echo "$off_state" | jq -r '.headerHidden')" = "false" ] \
+    && [ "$(echo "$off_state" | jq -r '.fabExists')" = "true" ] \
+    && [ "$(echo "$off_state" | jq -r '.fabHidden')" = "true" ] \
+    && [ "$(echo "$off_state" | jq -r '.fabDisplay // empty')" = "none" ] \
+    && [ "$(echo "$off_state" | jq -r '.fabRendered')" = "false" ] \
+    && [ "$(echo "$on_state" | jq -r '.fabHidden')" = "false" ] \
+    && [ "$(echo "$on_state" | jq -r '.fabDisplay // empty')" != "none" ] \
+    && [ "$(echo "$on_state" | jq -r '.fabRendered')" = "true" ] \
+    && [ "$(echo "$settings_open_state" | jq -r '.fabHidden')" = "true" ] \
+    && [ "$(echo "$settings_open_state" | jq -r '.fabDisplay // empty')" = "none" ] \
+    && [ "$(echo "$settings_open_state" | jq -r '.fabRendered')" = "false" ] \
+    && [ "$(echo "$click_result" | jq -r '.ok')" = "true" ] \
+    && [ "$(echo "$click_result" | jq -r '.target // empty')" = "fab" ] \
+    && [ "$(echo "$panel_state" | jq -r '.panelHidden')" = "false" ] \
+    && [ "$(echo "$panel_state" | jq -r '.panelTitle // empty')" = "回复主题" ]; then
+    passed=1
+    detail="off=$(echo "$off_state" | jq -c '{headerHidden, fabHidden, fabDisplay, fabRendered}') on=$(echo "$on_state" | jq -c '{fabHidden, fabDisplay, fabRendered}') settings=$(echo "$settings_open_state" | jq -c '{fabHidden, fabDisplay, fabRendered}') panel=$(echo "$panel_state" | jq -c '{panelHidden, panelTitle}')"
+  else
+    detail="off=$(echo "$off_state" | jq -c '{headerExists, headerText, headerHidden, fabExists, fabHidden, fabDisplay, fabRendered}') on=$(echo "$on_state" | jq -c '{fabHidden, fabDisplay, fabRendered}') settings=$(echo "$settings_open_state" | jq -c '{fabHidden, fabDisplay, fabRendered, panelHidden}') click=$(echo "$click_result" | jq -c '.') panel=$(echo "$panel_state" | jq -c '{panelHidden, panelTitle, headerExpanded, fabExpanded}')"
+  fi
+
+  if [ "$passed" -eq 1 ]; then
+    record_pass "$case_id" "$detail"
+  else
+    record_fail "$case_id" "$detail"
+  fi
+}
+
+run_015() {
+  local case_id="AGENT-CHROME-015"
+  local state
+
+  open_topic_by_index 0 >/dev/null || {
+    record_fail "$case_id" "无法打开抽屉"
+    return 0
+  }
+
+  state=$(toolbar_layout_state)
+
+  if [ "$(echo "$state" | jq -r '.toolbarExists')" = "true" ] \
+    && [ "$(echo "$state" | jq -r '.actionsExists')" = "true" ] \
+    && [ "$(echo "$state" | jq -r '.nowrapOk')" = "true" ] \
+    && [ "$(echo "$state" | jq -r '.widthOk')" = "true" ] \
+    && [ "$(echo "$state" | jq -r '.visibleCount')" -ge 5 ]; then
+    record_pass "$case_id" "items=$(echo "$state" | jq -c '.items | map({text, width, height, whiteSpace})')"
+  else
+    record_fail "$case_id" "state=$(echo "$state" | jq -c '{gridTemplateColumns, visibleCount, nowrapOk, widthOk, items}')"
+  fi
+}
+
 run_case() {
   local case_id=$1
   case "$case_id" in
@@ -991,6 +1243,8 @@ run_case() {
     AGENT-CHROME-009) run_009 ;;
     AGENT-CHROME-010) run_010 ;;
     AGENT-CHROME-013) run_013 ;;
+    AGENT-CHROME-014) run_014 ;;
+    AGENT-CHROME-015) run_015 ;;
     *)
       record_fail "$case_id" "未知用例 ID"
       ;;
diff --git a/src/content.css b/src/content.css
index 1f062b2..742ec58 100644
--- a/src/content.css
+++ b/src/content.css
@@ -199,9 +199,9 @@ body.ld-drawer-page-open #ld-drawer-root {
 #ld-drawer-root .ld-drawer-toolbar {
   display: grid;
   width: 100%;
-  grid-template-columns: auto minmax(0, 1fr);
+  grid-template-columns: minmax(0, 1fr);
   align-items: start;
-  gap: 8px 12px;
+  gap: 8px;
   min-width: 0;
 }
 
@@ -222,6 +222,7 @@ body.ld-drawer-page-open #ld-drawer-root {
 
 #ld-drawer-root .ld-drawer-actions {
   display: flex;
+  width: 100%;
   min-width: 0;
   align-items: center;
   flex-wrap: wrap;
@@ -231,6 +232,7 @@ body.ld-drawer-page-open #ld-drawer-root {
 
 #ld-drawer-root .ld-drawer-nav,
 #ld-drawer-root .ld-drawer-refresh,
+#ld-drawer-root .ld-drawer-reply-toggle,
 #ld-drawer-root .ld-drawer-link,
 #ld-drawer-root .ld-drawer-close,
 #ld-drawer-root .ld-drawer-settings-toggle,
@@ -245,6 +247,8 @@ body.ld-drawer-page-open #ld-drawer-root {
   line-height: 1;
   cursor: pointer;
   text-decoration: none;
+  white-space: nowrap;
+  flex: 0 0 auto;
 }
 
 #ld-drawer-root .ld-drawer-nav:disabled,
@@ -262,6 +266,7 @@ body.ld-drawer-page-open #ld-drawer-root {
 #ld-drawer-root .ld-drawer-close:hover,
 #ld-drawer-root .ld-drawer-nav:hover,
 #ld-drawer-root .ld-drawer-refresh:hover,
+#ld-drawer-root .ld-drawer-reply-toggle:hover,
 #ld-drawer-root .ld-drawer-link:hover,
 #ld-drawer-root .ld-drawer-settings-toggle:hover,
 #ld-drawer-root .ld-settings-close:hover,
@@ -276,6 +281,24 @@ body.ld-drawer-page-open #ld-drawer-root {
   background: color-mix(in srgb, var(--tertiary, #3b82f6) 10%, var(--secondary, #fff));
 }
 
+#ld-drawer-root .ld-drawer-reply-toggle {
+  border-color: color-mix(in srgb, var(--tertiary, #3b82f6) 30%, var(--primary-low, rgba(15, 23, 42, 0.12)));
+  background: color-mix(in srgb, var(--tertiary, #3b82f6) 10%, var(--secondary, #fff));
+  color: var(--tertiary, #3b82f6);
+  font-weight: 700;
+}
+
+#ld-drawer-root .ld-drawer-reply-toggle[aria-expanded="true"] {
+  border-color: var(--tertiary, #3b82f6);
+  background: color-mix(in srgb, var(--tertiary, #3b82f6) 16%, var(--secondary, #fff));
+}
+
+#ld-drawer-root .ld-drawer-reply-toggle:disabled,
+#ld-drawer-root .ld-drawer-reply-toggle.is-disabled {
+  opacity: 0.64;
+  cursor: not-allowed;
+}
+
 #ld-drawer-root .ld-drawer-settings {
   position: absolute;
   inset: 0;
@@ -399,6 +422,46 @@ body.ld-drawer-page-open #ld-drawer-root {
   background: color-mix(in srgb, var(--tertiary, #3b82f6) 64%, transparent);
 }
 
+#ld-drawer-root .ld-drawer-body,
+#ld-drawer-root .ld-drawer-settings-card,
+#ld-drawer-root .ld-drawer-reply-panel,
+#ld-drawer-root .ld-post-body pre {
+  overscroll-behavior: contain;
+}
+
+#ld-drawer-root .ld-drawer-body,
+#ld-drawer-root .ld-drawer-settings-card,
+#ld-drawer-root .ld-drawer-reply-panel {
+  scrollbar-width: thin;
+  scrollbar-color: color-mix(in srgb, var(--tertiary, #3b82f6) 40%, transparent) transparent;
+}
+
+#ld-drawer-root .ld-drawer-body::-webkit-scrollbar,
+#ld-drawer-root .ld-drawer-settings-card::-webkit-scrollbar,
+#ld-drawer-root .ld-drawer-reply-panel::-webkit-scrollbar {
+  width: 6px;
+  height: 6px;
+}
+
+#ld-drawer-root .ld-drawer-body::-webkit-scrollbar-track,
+#ld-drawer-root .ld-drawer-settings-card::-webkit-scrollbar-track,
+#ld-drawer-root .ld-drawer-reply-panel::-webkit-scrollbar-track {
+  background: transparent;
+}
+
+#ld-drawer-root .ld-drawer-body::-webkit-scrollbar-thumb,
+#ld-drawer-root .ld-drawer-settings-card::-webkit-scrollbar-thumb,
+#ld-drawer-root .ld-drawer-reply-panel::-webkit-scrollbar-thumb {
+  background: color-mix(in srgb, var(--tertiary, #3b82f6) 40%, transparent);
+  border-radius: 999px;
+}
+
+#ld-drawer-root .ld-drawer-body::-webkit-scrollbar-thumb:hover,
+#ld-drawer-root .ld-drawer-settings-card::-webkit-scrollbar-thumb:hover,
+#ld-drawer-root .ld-drawer-reply-panel::-webkit-scrollbar-thumb:hover {
+  background: color-mix(in srgb, var(--tertiary, #3b82f6) 64%, transparent);
+}
+
 #ld-drawer-root .ld-drawer-content {
   padding: 16px 18px 28px;
 }
@@ -439,6 +502,10 @@ body.ld-drawer-page-open #ld-drawer-root {
   transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
 }
 
+#ld-drawer-root .ld-drawer-reply-fab[hidden] {
+  display: none !important;
+}
+
 #ld-drawer-root .ld-drawer-reply-fab:hover {
   transform: translateY(calc(-50% - 1px));
   box-shadow: 0 18px 40px rgba(15, 23, 42, 0.22);
@@ -475,13 +542,14 @@ body.ld-drawer-page-open #ld-drawer-root {
 
 #ld-drawer-root .ld-drawer-reply-panel {
   position: absolute;
-  top: 50%;
+  top: calc(var(--ld-reply-panel-top, 84px) + 8px);
   right: 14px;
   z-index: 5;
   width: min(360px, calc(100% - 28px));
   display: grid;
   gap: 12px;
-  transform: translateY(-50%);
+  max-height: calc(100% - var(--ld-reply-panel-top, 84px) - 22px);
+  overflow: auto;
   padding: 14px;
   border: 1px solid var(--primary-low, rgba(15, 23, 42, 0.12));
   border-radius: 18px;
@@ -644,11 +712,14 @@ body.ld-drawer-page-open #ld-drawer-root {
 
 #ld-drawer-root .ld-post-actions {
   display: flex;
+  flex-wrap: wrap;
+  align-items: center;
   justify-content: flex-end;
+  gap: 8px;
   padding: 0 16px 14px;
 }
 
-#ld-drawer-root .ld-post-reply-button {
+#ld-drawer-root .ld-post-action-button {
   display: inline-flex;
   align-items: center;
   gap: 6px;
@@ -660,28 +731,55 @@ body.ld-drawer-page-open #ld-drawer-root {
   font-size: 12px;
   line-height: 1;
   cursor: pointer;
+  transition: border-color 0.18s ease, color 0.18s ease, background-color 0.18s ease, opacity 0.18s ease;
 }
 
-#ld-drawer-root .ld-post-reply-button:hover {
+#ld-drawer-root .ld-post-action-button:hover {
   border-color: var(--tertiary, #3b82f6);
   color: var(--tertiary, #3b82f6);
 }
 
-#ld-drawer-root .ld-post-reply-button-icon {
+#ld-drawer-root .ld-post-action-button.is-active {
+  border-color: color-mix(in srgb, var(--tertiary, #3b82f6) 32%, var(--primary-low, rgba(15, 23, 42, 0.12)));
+  background: color-mix(in srgb, var(--tertiary, #3b82f6) 10%, var(--secondary, #fff));
+  color: var(--tertiary, #3b82f6);
+}
+
+#ld-drawer-root .ld-post-action-button:disabled,
+#ld-drawer-root .ld-post-action-button.is-pending {
+  opacity: 0.68;
+  cursor: wait;
+}
+
+#ld-drawer-root .ld-post-action-button.is-feedback-error {
+  color: #b91c1c;
+  border-color: rgba(185, 28, 28, 0.2);
+  background: rgba(254, 226, 226, 0.72);
+}
+
+#ld-drawer-root .ld-post-action-button.is-icon-only {
+  padding-right: 8px;
+}
+
+#ld-drawer-root .ld-post-action-button-icon {
   width: 14px;
   height: 14px;
   display: inline-flex;
 }
 
-#ld-drawer-root .ld-post-reply-button-icon svg {
+#ld-drawer-root .ld-post-action-button-icon svg {
   width: 14px;
   height: 14px;
 }
 
-#ld-drawer-root .ld-post-reply-button-label {
+#ld-drawer-root .ld-post-action-button-label {
   white-space: nowrap;
 }
 
+#ld-drawer-root .ld-post-action-button-label:empty {
+  display: none;
+}
+
 #ld-drawer-root .ld-post-body > :first-child {
   margin-top: 0;
 }
@@ -929,6 +1027,7 @@ body.ld-drawer-page-open #ld-drawer-root {
     left: 12px;
     bottom: max(72px, env(safe-area-inset-bottom, 0px) + 56px);
     width: auto;
+    max-height: calc(100dvh - max(72px, env(safe-area-inset-bottom, 0px) + 56px) - 16px);
     transform: none;
   }
 }
diff --git a/src/content.js b/src/content.js
index 5f083ca..f406477 100644
--- a/src/content.js
+++ b/src/content.js
@@ -11,10 +11,15 @@
   const IMAGE_PREVIEW_SCALE_MAX = 4;
   const IMAGE_PREVIEW_SCALE_STEP = 0.2;
   const REPLY_UPLOAD_MARKER = "\u2063";
+  const POST_ACTION_TYPE_IDS = {
+    like: 2
+  };
   const DEFAULT_SETTINGS = {
     previewMode: "smart",
     postMode: "all",
+    authorFilter: "all",
     replyOrder: "default",
+    floatingReplyButton: "off",
     drawerWidth: "medium",
     drawerWidthCustom: 720,
     drawerMode: "push"
@@ -86,7 +91,8 @@
     meta: null,
     drawerBody: null,
     content: null,
-    replyButton: null,
+    replyToggleButton: null,
+    replyFabButton: null,
     replyPanel: null,
     replyPanelTitle: null,
     replyTextarea: null,
@@ -129,6 +135,7 @@
     replyUploadPendingCount: 0,
     replyUploadSerial: 0,
     replyComposerSessionId: 0,
+    deferOwnerFilterAutoLoad: false,
     lastLocation: location.href,
     settings: loadSettings(),
     isResizing: false,
@@ -173,6 +180,7 @@
               <button class="ld-drawer-nav" type="button" data-nav="next">下一帖</button>
               <button class="ld-drawer-settings-toggle" type="button" aria-expanded="false" aria-controls="ld-drawer-settings">选项</button>
               <button class="ld-drawer-refresh" type="button" aria-label="刷新最新回复" title="刷新最新回复" hidden>刷新</button>
+              <button class="ld-drawer-reply-toggle ld-drawer-reply-trigger" type="button" aria-expanded="false" aria-controls="ld-drawer-reply-panel" aria-label="回复当前主题" title="回复当前主题" hidden>回复主题</button>
               <a class="ld-drawer-link" href="https://linux.do/latest" target="_blank" rel="noopener noreferrer">新标签打开</a>
               <button class="ld-drawer-close" type="button" aria-label="关闭抽屉">关闭</button>
             </div>
@@ -198,6 +206,14 @@
                 <option value="first">仅首帖</option>
               </select>
             </label>
+            <label class="ld-setting-field">
+              <span class="ld-setting-label">作者过滤</span>
+              <select class="ld-setting-control" data-setting="authorFilter">
+                <option value="all">全部作者</option>
+                <option value="topicOwner">只看楼主</option>
+              </select>
+              <span class="ld-setting-hint">只在智能预览里过滤显示，不影响原帖内容</span>
+            </label>
             <label class="ld-setting-field">
               <span class="ld-setting-label">回复排序</span>
               <select class="ld-setting-control" data-setting="replyOrder">
@@ -206,6 +222,14 @@
               </select>
               <span class="ld-setting-hint">长帖下会优先显示最新一批回复，不代表把整帖一次性完整倒序</span>
             </label>
+            <label class="ld-setting-field">
+              <span class="ld-setting-label">悬浮回复入口</span>
+              <select class="ld-setting-control" data-setting="floatingReplyButton">
+                <option value="off">关闭</option>
+                <option value="on">开启</option>
+              </select>
+              <span class="ld-setting-hint">关闭后只保留头部的“回复主题”，开启后额外显示右侧悬浮快捷入口</span>
+            </label>
             <label class="ld-setting-field">
               <span class="ld-setting-label">抽屉模式</span>
               <select class="ld-setting-control" data-setting="drawerMode">
@@ -230,7 +254,7 @@
         <div class="ld-drawer-body">
           <div class="ld-drawer-content"></div>
         </div>
-        <button class="ld-drawer-reply-fab" type="button" aria-expanded="false" aria-controls="ld-drawer-reply-panel" aria-label="回复这个主题" title="回复这个主题">
+        <button class="ld-drawer-reply-fab ld-drawer-reply-trigger" type="button" aria-expanded="false" aria-controls="ld-drawer-reply-panel" aria-label="回复当前主题" title="回复当前主题">
           <span class="ld-drawer-reply-fab-icon" aria-hidden="true">
             <svg viewBox="0 0 24 24" focusable="false">
               <path d="M4 12.5c0-4.14 3.36-7.5 7.5-7.5h7a1.5 1.5 0 0 1 0 3h-7A4.5 4.5 0 0 0 7 12.5v1.38l1.44-1.44a1.5 1.5 0 0 1 2.12 2.12l-4 4a1.5 1.5 0 0 1-2.12 0l-4-4a1.5 1.5 0 1 1 2.12-2.12L4 13.88V12.5Z" fill="currentColor"></path>
@@ -267,7 +291,8 @@
     state.meta = root.querySelector(".ld-drawer-meta");
     state.drawerBody = root.querySelector(".ld-drawer-body");
     state.content = root.querySelector(".ld-drawer-content");
-    state.replyButton = root.querySelector(".ld-drawer-reply-fab");
+    state.replyToggleButton = root.querySelector(".ld-drawer-reply-toggle");
+    state.replyFabButton = root.querySelector(".ld-drawer-reply-fab");
     state.replyPanel = root.querySelector(".ld-drawer-reply-panel");
     state.replyPanelTitle = root.querySelector(".ld-reply-panel-title");
     state.replyTextarea = root.querySelector(".ld-reply-textarea");
@@ -292,7 +317,8 @@
     state.nextButton.addEventListener("click", () => navigateTopic(1));
     state.settingsToggle.addEventListener("click", toggleSettingsPanel);
     state.latestRepliesRefreshButton.addEventListener("click", handleLatestRepliesRefresh);
-    state.replyButton.addEventListener("click", toggleReplyPanel);
+    state.replyToggleButton.addEventListener("click", toggleReplyPanel);
+    state.replyFabButton.addEventListener("click", toggleReplyPanel);
     state.replyCancelButton.addEventListener("click", () => setReplyPanelOpen(false));
     state.replySubmitButton.addEventListener("click", handleReplySubmit);
     root.querySelector(".ld-reply-panel-close").addEventListener("click", () => setReplyPanelOpen(false));
@@ -343,7 +369,7 @@
       setSettingsPanelOpen(false);
     }
 
-    if (!state.replyPanel?.hidden && !target.closest(".ld-drawer-reply-panel") && !target.closest(".ld-drawer-reply-fab")) {
+    if (!state.replyPanel?.hidden && !target.closest(".ld-drawer-reply-panel") && !target.closest(".ld-drawer-reply-trigger")) {
       setReplyPanelOpen(false);
     }
 
@@ -503,6 +529,7 @@
     state.currentTargetSpec = null;
     state.currentTopic = null;
     state.currentLatestRepliesTopic = null;
+    state.deferOwnerFilterAutoLoad = false;
     state.loadMoreError = "";
     state.isLoadingMorePosts = false;
     state.isRefreshingLatestReplies = false;
@@ -552,6 +579,7 @@
     state.currentTopic = null;
     state.currentLatestRepliesTopic = null;
     state.currentTargetSpec = null;
+    state.deferOwnerFilterAutoLoad = false;
     state.isRefreshingLatestReplies = false;
     state.meta.textContent = "";
     state.loadMoreError = "";
@@ -893,6 +921,7 @@
     state.currentTargetSpec = targetSpec;
     state.currentTopicIdHint = typeof topic?.id === "number" ? topic.id : state.currentTopicIdHint;
     state.currentResolvedTargetPostNumber = resolvedTargetPostNumber;
+    state.deferOwnerFilterAutoLoad = shouldDeferOwnerFilterAutoLoad(viewModel);
     state.title.textContent = topic.title || fallbackTitle || "帖子预览";
     state.meta.textContent = buildTopicMeta(topic, viewModel.posts.length);
     state.content.replaceChildren(buildTopicView(topic, viewModel));
@@ -974,6 +1003,14 @@
       footer.appendChild(note);
     }
 
+    const authorFilterNote = buildAuthorFilterNote(viewModel, topicOwner);
+    if (authorFilterNote) {
+      const note = document.createElement("div");
+      note.className = "ld-topic-note";
+      note.textContent = authorFilterNote;
+      footer.appendChild(note);
+    }
+
     if (viewModel.hasHiddenPosts) {
       const note = document.createElement("div");
       note.className = "ld-topic-note";
@@ -1005,55 +1042,106 @@
     const moreAvailable = hasMoreTopicPosts(topic);
 
     if (state.settings.postMode === "first") {
-      return {
+      return applyAuthorFilterToViewModel({
         posts: posts.slice(0, 1),
         mode: "first",
         canAutoLoadMore: false,
         hasHiddenPosts: posts.length > 1 || moreAvailable
-      };
+      }, topic);
     }
 
     if (targetSpec?.targetPostNumber) {
-      return {
+      return applyAuthorFilterToViewModel({
         posts,
         mode: "targeted",
+        targetPostNumber: targetSpec.targetPostNumber,
         canAutoLoadMore: false,
         hasHiddenPosts: moreAvailable
-      };
+      }, topic);
     }
 
     if (state.settings.replyOrder !== "latestFirst" || posts.length <= 1) {
-      return {
+      return applyAuthorFilterToViewModel({
         posts,
         mode: "default",
         canAutoLoadMore: !targetSpec?.hasTarget,
         hasHiddenPosts: moreAvailable
-      };
+      }, topic);
     }
 
     if (topicHasCompletePostStream(topic)) {
-      return {
+      return applyAuthorFilterToViewModel({
         posts: [posts[0], ...posts.slice(1).reverse()],
         mode: "latestComplete",
         canAutoLoadMore: false,
         hasHiddenPosts: false
-      };
+      }, topic);
     }
 
     if (latestRepliesTopic) {
-      return {
+      return applyAuthorFilterToViewModel({
         posts: getLatestRepliesDisplayPosts(topic, latestRepliesTopic),
         mode: "latestWindow",
         canAutoLoadMore: false,
         hasHiddenPosts: moreAvailable
-      };
+      }, topic);
     }
 
-    return {
+    return applyAuthorFilterToViewModel({
       posts,
       mode: "latestUnavailable",
       canAutoLoadMore: false,
       hasHiddenPosts: moreAvailable
+    }, topic);
+  }
+
+  function applyAuthorFilterToViewModel(viewModel, topic) {
+    if (!viewModel || state.settings.authorFilter !== "topicOwner") {
+      return {
+        ...(viewModel || {}),
+        authorFilter: "all",
+        filterHiddenCount: 0,
+        filterUnavailable: false,
+        preservedTargetPostNumber: null
+      };
+    }
+
+    const topicOwner = getTopicOwnerIdentity(topic);
+    const sourcePosts = Array.isArray(viewModel.posts) ? viewModel.posts : [];
+    if (!topicOwner) {
+      return {
+        ...viewModel,
+        authorFilter: "topicOwner",
+        filterHiddenCount: 0,
+        filterUnavailable: true,
+        preservedTargetPostNumber: null
+      };
+    }
+
+    const targetPostNumber = viewModel.mode === "targeted" && Number.isFinite(viewModel.targetPostNumber)
+      ? Number(viewModel.targetPostNumber)
+      : null;
+    let preservedTargetPostNumber = null;
+    const filteredPosts = sourcePosts.filter((post) => {
+      if (isTopicOwnerPost(post, topicOwner)) {
+        return true;
+      }
+
+      if (targetPostNumber !== null && Number(post?.post_number) === targetPostNumber) {
+        preservedTargetPostNumber = targetPostNumber;
+        return true;
+      }
+
+      return false;
+    });
+    return {
+      ...viewModel,
+      posts: filteredPosts,
+      authorFilter: "topicOwner",
+      filterHiddenCount: Math.max(0, sourcePosts.length - filteredPosts.length),
+      filterUnavailable: false,
+      preservedTargetPostNumber,
+      hasHiddenPosts: Boolean(viewModel.hasHiddenPosts) || filteredPosts.length !== sourcePosts.length
     };
   }
 
@@ -1124,23 +1212,270 @@
     const actions = document.createElement("div");
     actions.className = "ld-post-actions";
 
-    const replyButton = document.createElement("button");
-    replyButton.type = "button";
-    replyButton.className = "ld-post-reply-button";
-    replyButton.setAttribute("aria-label", `回复第 ${post.post_number || "?"} 条`);
-    replyButton.innerHTML = `
-      <span class="ld-post-reply-button-icon" aria-hidden="true">
-        <svg viewBox="0 0 24 24" focusable="false">
+    actions.append(
+      buildLikeButton(post),
+      buildCopyLinkButton(post),
+      buildBookmarkButton(post),
+      buildReplyButton(post)
+    );
+    article.append(header, body, actions);
+    return article;
+  }
+
+  function buildLikeButton(post) {
+    const likeState = getPostLikeState(post);
+    const button = buildPostActionButton({
+      action: "like",
+      label: likeState.count > 0 ? likeState.count.toLocaleString() : "",
+      title: likeState.acted ? "取消点赞" : "点赞",
+      ariaLabel: likeState.acted ? "取消点赞这条" : "点赞这条",
+      isActive: likeState.acted,
+      isPressed: likeState.acted,
+      icon: `
+        <svg viewBox="0 0 24 24" focusable="false" aria-hidden="true">
+          <path d="M12.62 20.55a1.5 1.5 0 0 1-1.24 0C6.77 18.27 3 14.75 3 10.56 3 7.94 4.96 6 7.42 6c1.6 0 3.07.84 3.96 2.19A4.78 4.78 0 0 1 15.34 6C17.93 6 20 7.99 20 10.56c0 4.19-3.77 7.71-7.38 9.99Z" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linejoin="round"></path>
+        </svg>
+      `
+    });
+    button.addEventListener("click", () => handleLikeButtonClick(post, button));
+    return button;
+  }
+
+  function buildCopyLinkButton(post) {
+    const button = buildPostActionButton({
+      action: "copy-link",
+      label: "",
+      title: "复制本帖链接",
+      ariaLabel: "复制这条帖子链接",
+      icon: `
+        <svg viewBox="0 0 24 24" focusable="false" aria-hidden="true">
+          <path d="M10.5 13.5 13.5 10.5" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round"></path>
+          <path d="M8.4 15.6 6.7 17.3a3 3 0 1 1-4.24-4.24l3.53-3.53A3 3 0 0 1 10.2 13.8L9.1 14.9" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"></path>
+          <path d="m14.9 9.1 1.1-1.1a3 3 0 0 1 4.24 4.24l-3.53 3.53A3 3 0 0 1 12.48 12l1.7-1.7" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round"></path>
+        </svg>
+      `
+    });
+    button.addEventListener("click", () => handleCopyLinkButtonClick(post, button));
+    return button;
+  }
+
+  function buildBookmarkButton(post) {
+    const bookmarkState = getPostBookmarkState(post);
+    const button = buildPostActionButton({
+      action: "bookmark",
+      label: "",
+      title: bookmarkState.bookmarked ? "取消收藏" : "收藏",
+      ariaLabel: bookmarkState.bookmarked ? "取消收藏这条" : "收藏这条",
+      isActive: bookmarkState.bookmarked,
+      isPressed: bookmarkState.bookmarked,
+      icon: `
+        <svg viewBox="0 0 24 24" focusable="false" aria-hidden="true">
+          <path d="M7.25 4.75h9.5a1.5 1.5 0 0 1 1.5 1.5v13.05a.45.45 0 0 1-.72.36L12 15.54l-5.53 4.12a.45.45 0 0 1-.72-.36V6.25a1.5 1.5 0 0 1 1.5-1.5Z" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linejoin="round"></path>
+        </svg>
+      `
+    });
+    button.addEventListener("click", () => handleBookmarkButtonClick(post, button));
+    return button;
+  }
+
+  function buildReplyButton(post) {
+    const button = buildPostActionButton({
+      action: "reply",
+      label: "回复",
+      title: "回复这条",
+      ariaLabel: `回复第 ${post.post_number || "?"} 条`,
+      icon: `
+        <svg viewBox="0 0 24 24" focusable="false" aria-hidden="true">
           <path d="M4 12.5c0-4.14 3.36-7.5 7.5-7.5h7a1.5 1.5 0 0 1 0 3h-7A4.5 4.5 0 0 0 7 12.5v1.38l1.44-1.44a1.5 1.5 0 0 1 2.12 2.12l-4 4a1.5 1.5 0 0 1-2.12 0l-4-4a1.5 1.5 0 1 1 2.12-2.12L4 13.88V12.5Z" fill="currentColor"></path>
         </svg>
-      </span>
-      <span class="ld-post-reply-button-label">回复这条</span>
-    `;
-    replyButton.addEventListener("click", () => openReplyPanelForPost(post));
+      `
+    });
+    button.addEventListener("click", () => openReplyPanelForPost(post));
+    return button;
+  }
 
-    actions.appendChild(replyButton);
-    article.append(header, body, actions);
-    return article;
+  function buildPostActionButton(options = {}) {
+    const button = document.createElement("button");
+    button.type = "button";
+    button.className = "ld-post-action-button";
+    if (options.action) {
+      button.dataset.action = options.action;
+    }
+    if (options.isActive) {
+      button.classList.add("is-active");
+    }
+    if (!options.label) {
+      button.classList.add("is-icon-only");
+    }
+    if (options.title) {
+      button.title = options.title;
+    }
+    if (options.ariaLabel) {
+      button.setAttribute("aria-label", options.ariaLabel);
+    }
+    if (typeof options.isPressed === "boolean") {
+      button.setAttribute("aria-pressed", String(options.isPressed));
+    }
+
+    const icon = document.createElement("span");
+    icon.className = "ld-post-action-button-icon";
+    icon.innerHTML = options.icon || "";
+
+    const label = document.createElement("span");
+    label.className = "ld-post-action-button-label";
+    label.textContent = options.label || "";
+
+    button.append(icon, label);
+    return button;
+  }
+
+  function getPostLikeState(post) {
+    const summary = getPostActionSummary(post, POST_ACTION_TYPE_IDS.like);
+    return {
+      count: normalizeCount(summary?.count ?? post?.like_count) || 0,
+      acted: Boolean(summary?.acted),
+      canToggle: Boolean(summary?.acted) || summary?.can_act !== false
+    };
+  }
+
+  function getPostBookmarkState(post) {
+    const bookmarkId = Number(post?.bookmark_id);
+    return {
+      bookmarked: Boolean(post?.bookmarked),
+      bookmarkId: Number.isFinite(bookmarkId) ? bookmarkId : null
+    };
+  }
+
+  function getPostActionSummary(post, actionTypeId) {
+    if (!Array.isArray(post?.actions_summary)) {
+      return null;
+    }
+
+    return post.actions_summary.find((summary) => Number(summary?.id) === Number(actionTypeId)) || null;
+  }
+
+  async function handleLikeButtonClick(post, button) {
+    const likeState = getPostLikeState(post);
+    if (!likeState.canToggle) {
+      showPostActionFeedback(button, "不可用", true);
+      return;
+    }
+
+    await runPostAction(button, async () => {
+      const updatedPost = likeState.acted
+        ? await destroyPostLike(post)
+        : await createPostLike(post);
+      applyUpdatedPostToCurrentView(updatedPost);
+    });
+  }
+
+  async function handleCopyLinkButtonClick(post, button) {
+    try {
+      await writeClipboardText(buildPostPermalink(post));
+      showPostActionFeedback(button, "已复制");
+    } catch (error) {
+      showPostActionFeedback(button, error?.message || "复制失败", true);
+    }
+  }
+
+  async function handleBookmarkButtonClick(post, button) {
+    await runPostAction(button, async () => {
+      const bookmarkState = getPostBookmarkState(post);
+      const updatedPost = bookmarkState.bookmarked
+        ? await destroyPostBookmark(post, bookmarkState.bookmarkId)
+        : await createPostBookmark(post);
+      applyUpdatedPostToCurrentView(updatedPost);
+    });
+  }
+
+  async function runPostAction(button, action) {
+    if (!(button instanceof HTMLButtonElement) || button.disabled) {
+      return;
+    }
+
+    button.disabled = true;
+    button.classList.add("is-pending");
+
+    try {
+      await action();
+    } catch (error) {
+      showPostActionFeedback(button, error?.message || "操作失败", true);
+    } finally {
+      button.disabled = false;
+      button.classList.remove("is-pending");
+    }
+  }
+
+  function showPostActionFeedback(button, message, isError = false) {
+    if (!(button instanceof HTMLButtonElement)) {
+      return;
+    }
+
+    const label = button.querySelector(".ld-post-action-button-label");
+    if (!(label instanceof HTMLElement)) {
+      return;
+    }
+
+    window.clearTimeout(Number(button.dataset.feedbackTimer || 0));
+    const originalText = button.dataset.originalLabel ?? label.textContent ?? "";
+    button.dataset.originalLabel = originalText;
+    label.textContent = message || "";
+    button.classList.toggle("is-feedback-error", isError);
+    button.classList.remove("is-icon-only");
+
+    const timer = window.setTimeout(() => {
+      if (!button.isConnected) {
+        return;
+      }
+
+      label.textContent = button.dataset.originalLabel || "";
+      button.classList.toggle("is-icon-only", !label.textContent);
+      button.classList.remove("is-feedback-error");
+      button.dataset.feedbackTimer = "";
+    }, 1400);
+
+    button.dataset.feedbackTimer = String(timer);
+  }
+
+  function buildPostPermalink(post) {
+    const currentUrl = state.currentUrl || location.href;
+    const url = new URL(currentUrl, location.href);
+    const parsed = parseTopicPath(url.pathname, state.currentTopicIdHint);
+    url.pathname = parsed?.topicPath || stripTrailingSlash(url.pathname);
+    url.search = "";
+    url.hash = "";
+
+    if (Number.isFinite(post?.post_number) && post.post_number > 1) {
+      url.pathname = `${url.pathname}/${post.post_number}`;
+    }
+
+    return url.toString().replace(/\/$/, "");
+  }
+
+  async function writeClipboardText(text) {
+    if (navigator.clipboard?.writeText) {
+      await navigator.clipboard.writeText(text);
+      return;
+    }
+
+    const textarea = document.createElement("textarea");
+    textarea.value = text;
+    textarea.setAttribute("readonly", "true");
+    textarea.style.position = "fixed";
+    textarea.style.opacity = "0";
+    textarea.style.pointerEvents = "none";
+    textarea.style.left = "-9999px";
+    document.body.appendChild(textarea);
+    textarea.select();
+
+    try {
+      const copied = document.execCommand("copy");
+      if (!copied) {
+        throw new Error("复制失败");
+      }
+    } finally {
+      textarea.remove();
+    }
   }
 
   function handleDrawerBodyScroll() {
@@ -1168,8 +1503,16 @@
     setReplyPanelOpen(true);
   }
 
+  function forEachReplyTriggerButton(callback) {
+    for (const button of [state.replyToggleButton, state.replyFabButton]) {
+      if (button instanceof HTMLButtonElement) {
+        callback(button);
+      }
+    }
+  }
+
   function setReplyPanelOpen(isOpen) {
-    if (!state.replyPanel || !state.replyButton) {
+    if (!state.replyPanel) {
       return;
     }
 
@@ -1178,7 +1521,9 @@
     }
 
     state.replyPanel.hidden = !isOpen;
-    state.replyButton.setAttribute("aria-expanded", String(isOpen));
+    forEachReplyTriggerButton((button) => {
+      button.setAttribute("aria-expanded", String(isOpen));
+    });
 
     if (!isOpen) {
       setReplyTarget(null);
@@ -1588,6 +1933,11 @@
       return;
     }
 
+    if (state.deferOwnerFilterAutoLoad && state.drawerBody.scrollTop <= 0) {
+      updateLoadMoreStatus();
+      return;
+    }
+
     const remainingDistance = state.drawerBody.scrollHeight - state.drawerBody.scrollTop - state.drawerBody.clientHeight;
     if (remainingDistance > LOAD_MORE_TRIGGER_OFFSET) {
       updateLoadMoreStatus();
@@ -1766,28 +2116,34 @@
   }
 
   function handleDrawerRootWheel(event) {
-    if (state.imagePreview?.hidden) {
-      return;
-    }
-
     const target = event.target;
-    if (!(target instanceof Element) || !target.closest(".ld-image-preview-stage")) {
+    if (!(target instanceof Element)) {
       return;
     }
 
-    event.preventDefault();
+    if (!state.imagePreview?.hidden && target.closest(".ld-image-preview-stage")) {
+      event.preventDefault();
 
-    const nextScale = clampImagePreviewScale(
-      state.imagePreviewScale + (event.deltaY < 0 ? IMAGE_PREVIEW_SCALE_STEP : -IMAGE_PREVIEW_SCALE_STEP)
-    );
+      const nextScale = clampImagePreviewScale(
+        state.imagePreviewScale + (event.deltaY < 0 ? IMAGE_PREVIEW_SCALE_STEP : -IMAGE_PREVIEW_SCALE_STEP)
+      );
+
+      if (nextScale === state.imagePreviewScale) {
+        return;
+      }
 
-    if (nextScale === state.imagePreviewScale) {
+      updateImagePreviewTransformOrigin(event.clientX, event.clientY);
+      state.imagePreviewScale = nextScale;
+      applyImagePreviewScale();
       return;
     }
 
-    updateImagePreviewTransformOrigin(event.clientX, event.clientY);
-    state.imagePreviewScale = nextScale;
-    applyImagePreviewScale();
+    if (event.deltaY <= 0 || !target.closest(".ld-drawer-body") || !shouldLoadMoreFromOwnerFilterWheel()) {
+      return;
+    }
+
+    event.preventDefault();
+    loadMorePosts().catch(() => {});
   }
 
   function resetImagePreviewScale() {
@@ -1858,6 +2214,7 @@
     state.currentLatestRepliesTopic = null;
     state.currentTargetSpec = null;
     state.currentResolvedTargetPostNumber = null;
+    state.deferOwnerFilterAutoLoad = false;
     state.isLoadingMorePosts = false;
     state.isRefreshingLatestReplies = false;
     state.isReplySubmitting = false;
@@ -1892,6 +2249,7 @@
     state.currentLatestRepliesTopic = null;
     state.currentTargetSpec = null;
     state.currentResolvedTargetPostNumber = null;
+    state.deferOwnerFilterAutoLoad = false;
     state.isLoadingMorePosts = false;
     state.isRefreshingLatestReplies = false;
     state.isReplySubmitting = false;
@@ -2094,6 +2452,27 @@
     return "";
   }
 
+  function buildAuthorFilterNote(viewModel, topicOwner) {
+    if (viewModel.authorFilter !== "topicOwner") {
+      return "";
+    }
+
+    if (viewModel.filterUnavailable || !topicOwner) {
+      return `当前已切到\u201C只看楼主\u201D模式，但这次没识别出楼主身份，暂按当前结果显示。`;
+    }
+
+    const ownerLabel = topicOwner.displayUsername ? `@${topicOwner.displayUsername}` : "楼主";
+    if (Number.isFinite(viewModel.preservedTargetPostNumber)) {
+      return `当前为\u201C只看楼主\u201D模式，已保留当前定位的 #${viewModel.preservedTargetPostNumber}，其余仅显示 ${ownerLabel} 的发言。`;
+    }
+
+    if (!viewModel.posts.length && viewModel.canAutoLoadMore) {
+      return `当前为\u201C只看楼主\u201D模式，已加载范围内还没有 ${ownerLabel} 的更多发言，继续下滑会继续尝试加载。`;
+    }
+
+    return `当前为\u201C只看楼主\u201D模式，仅显示 ${ownerLabel} 的发言。`;
+  }
+
   function getLatestRepliesTopicUrl(topicUrl, topicIdHint = null) {
     const url = new URL(topicUrl);
     const parsed = parseTopicPath(url.pathname, topicIdHint);
@@ -2344,6 +2723,172 @@
     return /\.(avif|bmp|gif|jpe?g|png|svg|webp)$/i.test(String(fileName || ""));
   }
 
+  async function createPostLike(post) {
+    const response = await fetch(`${location.origin}/post_actions.json`, {
+      method: "POST",
+      credentials: "include",
+      headers: buildAuthenticatedFormHeaders(),
+      body: buildFormBody({
+        id: post?.id,
+        post_action_type_id: POST_ACTION_TYPE_IDS.like
+      })
+    });
+
+    return parsePostActionResponse(response);
+  }
+
+  async function destroyPostLike(post) {
+    const url = new URL(`${location.origin}/post_actions/${post?.id}.json`);
+    url.searchParams.set("post_action_type_id", String(POST_ACTION_TYPE_IDS.like));
+
+    const response = await fetch(url.toString(), {
+      method: "DELETE",
+      credentials: "include",
+      headers: buildAuthenticatedFormHeaders()
+    });
+
+    return parsePostActionResponse(response);
+  }
+
+  async function createPostBookmark(post) {
+    const response = await fetch(`${location.origin}/bookmarks.json`, {
+      method: "POST",
+      credentials: "include",
+      headers: buildAuthenticatedFormHeaders(),
+      body: buildFormBody({
+        bookmarkable_id: post?.id,
+        bookmarkable_type: "Post"
+      })
+    });
+
+    await parseMutationResponse(response);
+    return refreshSinglePostState(post);
+  }
+
+  async function destroyPostBookmark(post, bookmarkId) {
+    if (!Number.isFinite(bookmarkId)) {
+      throw new Error("未找到收藏记录，请刷新后重试");
+    }
+
+    const response = await fetch(`${location.origin}/bookmarks/${bookmarkId}.json`, {
+      method: "DELETE",
+      credentials: "include",
+      headers: buildAuthenticatedFormHeaders()
+    });
+
+    await parseMutationResponse(response);
+    return refreshSinglePostState(post);
+  }
+
+  async function refreshSinglePostState(post) {
+    const posts = await fetchTopicPostsBatch(state.currentUrl, [post?.id], undefined, state.currentTopicIdHint);
+    const refreshedPost = posts.find((item) => item?.id === post?.id || item?.post_number === post?.post_number);
+    if (!refreshedPost) {
+      throw new Error("刷新帖子状态失败");
+    }
+    return refreshedPost;
+  }
+
+  function buildAuthenticatedFormHeaders() {
+    const csrfToken = getCsrfToken();
+    if (!csrfToken) {
+      throw new Error("未找到登录令牌，请刷新页面后重试");
+    }
+
+    return {
+      Accept: "application/json",
+      "Content-Type": "application/x-www-form-urlencoded; charset=UTF-8",
+      "X-Requested-With": "XMLHttpRequest",
+      "X-CSRF-Token": csrfToken
+    };
+  }
+
+  function buildFormBody(values) {
+    const body = new URLSearchParams();
+    for (const [key, value] of Object.entries(values || {})) {
+      if (value === null || value === undefined || value === "") {
+        continue;
+      }
+
+      body.set(key, String(value));
+    }
+    return body;
+  }
+
+  async function parsePostActionResponse(response) {
+    const data = await parseMutationResponse(response);
+    if (!data || typeof data !== "object" || !Number.isFinite(Number(data.id))) {
+      throw new Error("帖子状态返回异常");
+    }
+
+    return data;
+  }
+
+  async function parseMutationResponse(response) {
+    const contentType = response.headers.get("content-type") || "";
+    const data = contentType.includes("json")
+      ? await response.json()
+      : null;
+
+    if (!response.ok) {
+      const message = Array.isArray(data?.errors) && data.errors.length > 0
+        ? data.errors.join("；")
+        : (data?.error || data?.message || `Unexpected response: ${response.status}`);
+      throw new Error(message);
+    }
+
+    return data;
+  }
+
+  function applyUpdatedPostToCurrentView(updatedPost) {
+    if (!updatedPost || !state.currentTopic) {
+      return;
+    }
+
+    const previousScrollTop = state.drawerBody?.scrollTop || 0;
+    const nextTopic = replaceTopicPost(state.currentTopic, updatedPost);
+    const nextLatestRepliesTopic = replaceTopicPost(state.currentLatestRepliesTopic, updatedPost);
+
+    renderTopic(nextTopic, state.currentUrl, state.currentFallbackTitle, state.currentResolvedTargetPostNumber, {
+      latestRepliesTopic: nextLatestRepliesTopic,
+      targetSpec: state.currentTargetSpec,
+      preserveScrollTop: previousScrollTop
+    });
+  }
+
+  function replaceTopicPost(topic, nextPost) {
+    if (!topic || !nextPost) {
+      return topic;
+    }
+
+    const posts = topic?.post_stream?.posts || [];
+    const nextPostId = Number(nextPost.id);
+    const nextPostNumber = Number(nextPost.post_number);
+    let replaced = false;
+    const nextPosts = posts.map((post) => {
+      const sameId = Number.isFinite(nextPostId) && Number(post?.id) === nextPostId;
+      const samePostNumber = Number.isFinite(nextPostNumber) && Number(post?.post_number) === nextPostNumber;
+      if (sameId || samePostNumber) {
+        replaced = true;
+        return nextPost;
+      }
+      return post;
+    });
+
+    if (!replaced) {
+      nextPosts.push(nextPost);
+      nextPosts.sort((left, right) => Number(left?.post_number || 0) - Number(right?.post_number || 0));
+    }
+
+    return {
+      ...topic,
+      post_stream: {
+        ...(topic.post_stream || {}),
+        posts: nextPosts
+      }
+    };
+  }
+
   function getCsrfToken() {
     const token = document.querySelector('meta[name="csrf-token"]')?.getAttribute("content") || "";
     return token.trim();
@@ -2810,6 +3355,15 @@
     return parts.join(" · ");
   }
 
+  function normalizeCount(value) {
+    const numeric = Number(value);
+    if (!Number.isFinite(numeric) || numeric < 0) {
+      return null;
+    }
+
+    return Math.round(numeric);
+  }
+
   function formatDate(value) {
     try {
       return new Intl.DateTimeFormat("zh-CN", {
@@ -2847,6 +3401,14 @@
         settings.drawerMode = DEFAULT_SETTINGS.drawerMode;
       }
 
+      if (settings.authorFilter !== "all" && settings.authorFilter !== "topicOwner") {
+        settings.authorFilter = DEFAULT_SETTINGS.authorFilter;
+      }
+
+      if (settings.floatingReplyButton !== "off" && settings.floatingReplyButton !== "on") {
+        settings.floatingReplyButton = DEFAULT_SETTINGS.floatingReplyButton;
+      }
+
       settings.drawerWidthCustom = clampDrawerWidth(settings.drawerWidthCustom);
       return settings;
     } catch {
@@ -2880,12 +3442,23 @@
     const hasTopic = Boolean(state.currentTopic?.id);
     const isTargetedReply = Number.isFinite(state.replyTargetPostNumber);
     const isReplyUploading = state.replyUploadPendingCount > 0;
+    const hasCurrentUrl = Boolean(state.currentUrl);
     const isIframeMode = state.root?.classList.contains(IFRAME_MODE_CLASS);
+    const isSettingsOpen = !state.settingsPanel?.hidden;
+
+    if (state.replyToggleButton) {
+      state.replyToggleButton.hidden = !hasCurrentUrl || isIframeMode;
+      state.replyToggleButton.disabled = !hasTopic || state.isReplySubmitting;
+      state.replyToggleButton.classList.toggle("is-disabled", !hasTopic || state.isReplySubmitting);
+    }
 
-    if (state.replyButton) {
-      state.replyButton.hidden = !Boolean(state.currentUrl) || isIframeMode;
-      state.replyButton.disabled = !hasTopic || state.isReplySubmitting;
-      state.replyButton.classList.toggle("is-disabled", !hasTopic || state.isReplySubmitting);
+    if (state.replyFabButton) {
+      state.replyFabButton.hidden = !hasCurrentUrl
+        || isIframeMode
+        || isSettingsOpen
+        || state.settings.floatingReplyButton !== "on";
+      state.replyFabButton.disabled = !hasTopic || state.isReplySubmitting;
+      state.replyFabButton.classList.toggle("is-disabled", !hasTopic || state.isReplySubmitting);
     }
 
     if (state.replyTextarea) {
@@ -2952,12 +3525,14 @@
     }
 
     if (isOpen) {
+      setReplyPanelOpen(false);
       updateSettingsPopoverPosition();
       queueMicrotask(() => state.settingsCard?.querySelector(".ld-setting-control")?.focus());
     }
 
     state.settingsPanel.hidden = !isOpen;
     state.settingsToggle.setAttribute("aria-expanded", String(isOpen));
+    syncReplyUI();
   }
 
   function handleSettingsChange(event) {
@@ -2987,6 +3562,12 @@
       return;
     }
 
+    if (key === "floatingReplyButton") {
+      syncReplyUI();
+      setSettingsPanelOpen(false);
+      return;
+    }
+
     refreshCurrentView();
     setSettingsPanelOpen(false);
   }
@@ -2997,6 +3578,7 @@
     saveSettings();
     applyDrawerWidth();
     applyDrawerMode();
+    syncReplyUI();
     refreshCurrentView();
     setSettingsPanelOpen(false);
   }
@@ -3074,12 +3656,35 @@
     applyDrawerWidth();
   }
 
+  function shouldDeferOwnerFilterAutoLoad(viewModel) {
+    return Boolean(
+      viewModel
+      && viewModel.authorFilter === "topicOwner"
+      && viewModel.canAutoLoadMore
+      && Number(viewModel.filterHiddenCount || 0) > 0
+    );
+  }
+
+  function shouldLoadMoreFromOwnerFilterWheel() {
+    if (!state.deferOwnerFilterAutoLoad || !state.drawerBody || !state.currentTopic || state.isLoadingMorePosts) {
+      return false;
+    }
+
+    if (state.settings.postMode === "first" || state.settings.replyOrder === "latestFirst" || state.currentTargetSpec?.hasTarget || !hasMoreTopicPosts(state.currentTopic)) {
+      return false;
+    }
+
+    return state.drawerBody.scrollHeight - state.drawerBody.clientHeight <= LOAD_MORE_TRIGGER_OFFSET;
+  }
+
   function updateSettingsPopoverPosition() {
     if (!state.header || !state.settingsPanel) {
       return;
     }
 
-    state.root.style.setProperty("--ld-settings-top", `${state.header.offsetHeight + 8}px`);
+    const offset = `${state.header.offsetHeight + 8}px`;
+    state.root.style.setProperty("--ld-settings-top", offset);
+    state.root.style.setProperty("--ld-reply-panel-top", offset);
   }
 
   function scheduleTopicTrackerPositionSync() {