Monaco's underlying textarea, and content, can get out of sync when native undo is used

[issacgerges]

monaco-editor version: 0.19.3
Browser: Chrome and Chromium
OS: MacOS

When using Chrome's system menus to undo/redo the textarea that backs monaco can become out of sync with the editor content.

Repro

When unfocusing and recfocusing Chrome via cmd+~, the editor fails to respond to undo and redo events. I've added the following css to unhide the underlying textarea

textarea.inputarea {
    width: 100px !important;
    color: white !important;
    background: rgb(150, 114, 236) !important;
};

Suggestions

I'm unfamiliar with monaco but believe this issue could be fixed by also explicitly attaching a change handler to the textarea (which I've verified does fire in this case)

[rebornix]

Thanks for the report. I only see this issue with standalone editor but not VS Code.

[rebornix]

My fix doesn't really fix the problem and the native undo/redo is poorly supported with standalone, including Safari.

Another case:

• Open https://microsoft.github.io/monaco-editor/
• Delete a character from one Monaco editor
• Menu -> Edit -> Undo

If you close a tab right before, you can see the menu item is "Undo closing tab". Our changes to the textarea is not picked up by the native undo/redo stack.