Using a mouse wheel to scroll (keyboard page up/down nav is fine), and the doc isn’t large at all - anything that exceeds the input height. Before taking the Chrome update, a normal finger scroll on the wheel might scroll 50 lines in the Codemirror input, after the update the same gesture scrolls maybe 3 lines.
Also seen using Microsoft Edge (Chromium) v 94.0.992.31 - scrolling is worse there, with the same gesture scrolling fewer than 2 lines.
No issue w/ Firefox.
I currently see the issue on the codemirror site, in the Github online editor, and in ServiceNow’s script fields (all use Codemirror).
I suspect there’s nothing you can do except maybe file a Chromium bug. I can get a bunch of folks to star an issue, but I personally wouldn’t know the best way to most helpfully describe the issue for the Chromium dev team.