Select All not working properly in Chrome (and Safari)

[cmcisaac6]

Describe the issue

In a moderately large document, in Chrome and Safari, right-clicking and then clicking "Select All" does not select the whole document. The same applies when using the browser menu to Edit > Select All, but not when using the keyboard shortcut Ctrl+A or Cmd+A.

In the example video shown, if the cursor is within the first 62 lines, it will select the first 62 lines only. If the cursor is after that, then it won't select anything

It looks like a similar issue was reported recently on iOS Safari #1304.

There's also an older issue related to this on Safari, but that was marked as a browser bug #1052. This suggests that it was previously working ok on Chrome.

Screen.Recording.2024-01-11.at.15.39.27.mov

Browser and platform

Chrome 120.0.6099.129, Safari 16.6 on macOS 13.5 and also reproduced on Windows.

Reproduction link

https://codemirror.net/try/?c=aW1wb3J0IHttaW5pbWFsU2V0dXAsIEVkaXRvclZpZXd9IGZyb20gImNvZGVtaXJyb3IiCgpjb25zdCBsaW5lcyA9IFtdCgpmb3IgKGxldCBpID0gMDsgaSA8IDUwMDsgaSsrKSB7CiAgbGluZXMucHVzaChgTGluZSAke2l9YCkKfQoKbmV3IEVkaXRvclZpZXcoewogIGRvYzogbGluZXMuam9pbignXG4nKSwKICBleHRlbnNpb25zOiBtaW5pbWFsU2V0dXAsCiAgcGFyZW50OiBkb2N1bWVudC5ib2R5Cn0pCg==

[marijnh]

This patch extends the iOS patch to also cover Chrome's behavior here.