TimeZone Changer

TimeZone Changer is a Chrome extension (Manifest V3) that aligns browser timezone behavior with your network/IP location, while giving full per-site and per-tab control over spoofing.

Highlights (v2.01)

• Automatic timezone detection by IP (ipwho.is, freeipapi.com)
• Domain exclusions with wildcard support (*.domain.com)
• Whitelist mode support
• Per-site rules:
  • Do not spoof
  • Fixed timezone
  • Auto by IP
• Per-tab overrides (session-scoped)
• Tab-lifetime timezone lock in auto mode (stable behavior while tab is open)
• Safe patching strategy (Proxy-based where possible)
• Popup and Options UI for rule management

Default Protected Domains

Spoofing is disabled by default on critical Google/Gemini domains to avoid breaking uploads and auth flows:

• *.google.com
• gemini.google.com
• *.googleapis.com
• upload.googleapis.com
• *.gstatic.com
• accounts.google.com

On these hosts the extension falls back to real system timezone behavior.

Rule Priority

Rules are resolved in this order:

1. Per-tab override
2. Per-site rule
3. Exclusion / whitelist decision
4. Global default mode (auto)

Storage Model

• chrome.storage.sync: settings, domain lists, site rules
• chrome.storage.local: runtime IP/timezone metadata
• chrome.storage.session: per-tab temporary state (lock/override)

UI

• Popup
  • Current timezone/IP/location status
  • Current host + active mode
  • Quick action: add current site to exclusions
  • Quick per-site and per-tab mode controls
• Options page
  • Manage excluded domains
  • Manage whitelist domains
  • Manage per-site rules

Installation

1. Clone or download this repository.
2. Open chrome://extensions/.
3. Enable Developer mode.
4. Click Load unpacked.
5. Select the project folder.

Technical Notes

• Uses content-script + page-context injection model
• Checks location.hostname before applying spoof logic
• Supports all frames (all_frames: true)
• Maintains MV3 compatibility

License

MIT. See LICENSE.