fit-textarea causing significant slow down when adding PR review comments

[gmaclennan]

Browser: Safari 14.0.3
Example URL: https://github.com/digidem/mapeo-mobile/pull/566/files#

When reviewing a PR and adding a code comment with multiple lines, refined github causes a slowdown that results in a typing appearing on the screen a second or so after keys are pressed.

I ran the profiler on the page and identified that each keypress is calling the fitTextArea() function and takes ~5ms.

Turning off the fit-textarea feature resolves the problem and typing is not delayed any more.

[yakov116]

Will be fixed in the next release

[fregante]

Confirmed and hopefully it will be fixed in the next release. I don’t know when that’ll happen in Safari because releases aren’t automated there yet #3686

[fregante]

For the time being, yes, disabling the feature is highly advised. I had to do the same for the past few months.

[fregante]

We had to re-enable it due to #4275 unfortunately

[fregante]

Closing because of #4447

I'd basically need to rewrite or replace fit-textareas to enable the feature everywhere:

• Use rows fregante/fit-textarea#21