Add a warning about lack of devtool support (#4803)

* Add a warning about lack of devtool support

* Update virtualview.md

* Update docs/virtualview.md

Co-authored-by: Ruslan Lesiutin <28902667+hoxyq@users.noreply.github.com>

* Update virtualview.md

reordering some words

---------

Co-authored-by: Ruslan Lesiutin <28902667+hoxyq@users.noreply.github.com>

Author: lunaleaps

docs/virtualview.md

@@ -41,6 +41,13 @@ Blocking the main thread can provide a better user experience by preventing flas
 
 However, blocking the main thread also comes with tradeoffs. If an update operation, such as mounting the children of a `VirtualView`, takes too long to finish, it can now drop frames. Dropping more than a couple frames can lead to a worse user experience by making the app feel sluggish and non-responsive. Dropping too many frames may cause the operating system to display a modal indicating the app is not responsive, or it may even terminate your app!
 
+:::warning
+DevTools does not currently support debugging JavaScript on the main thread. This means if you are using breakpoints to debug code called from `onModeChange`, that is executed on the main thread, your debugger may freeze.
+
+Debugging all other parts of your JavaScript code should work as expected. We are working on closing this gap before releasing `VirtualView` to stable channels of React Native.
+:::
+
+
 ### Prerendering
 
 `VirtualView` enables you to benefit from main thread rendering while mitigating the disadvantages of dropped frames by rendering earlier before it is needed. This is called “prerendering”.