Viewport resets itself randomly in long documents

[nabati]

Repro:

1. Create a note with Markdown Basic as the editor.
2. Paste the snippet below:

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3. Try editing it half-way down. Repeat multiple times at different location. At some point you will notice that the editor viewport will jump so that the caret is at the top of the viewport (note, the caret is still in the right place, it's just the viewport that jumps).

It doesn't happen consistently, but it happens often enough to be incredibly disruptive.

You see this behaviour at the end of this GIF:

[moughxyz]

Can replicate, thanks!

[TheodoreChu]

I'm not sure what's causing this issue. I'm also experiencing it with the Append Editor. Do you have any ideas @ningsongshen?

[ningsongshen]

Hm I'm having trouble replicating it...but I looked at the code and there seems to be a couple areas that handle scrolling (that are not in other editors, like the Bold Editor)