User menu takes a long time to open/close

[david-crespo]

Weird one. Can repro locally. Seems like it's only on the homepage, which points to something about the cost of re-rendering the whole page? (which shouldn't be happening)

Update: it's not rendering the page, but it may still have something to do with the size of the page, maybe the cost of applying background opacity when the dropdown appears. When I type something in the filter box and make the list a lot shorter, the delay disappears.

https://twitter.com/shadcn/status/1672620192663478273

[benjaminleonard]

Wonder if this is related to the bug Eugene had where the select was taking a long time to open? Both radix

[david-crespo]

Well, I turned off all the CSS and it's instantaneous. So that's a pretty strong hint.

[david-crespo]

A couple more details:

• Much faster in Chrome
• Commenting out this line in particular improves the delay by maybe 80% but doesn't eliminate it

https://github.com/oxidecomputer/rfd-site/blob/3688a8caae57b72accb3deac17737b65d4723344/app/styles/index.css#L2

• It doesn't have to do with the height of the index page alone, because replacing the RFD rows with empty boxes of the same height fixes the problem

[david-crespo]

Ok. I'm like 80% sure it's that P3 colors are just slow, possibly when doing anything, possibly only when combined with some kind of opacity filter.

[benjaminleonard]

Well there shouldn't be any opacity being applied whilst the dropdown is open. It doesn't seem too bad for me (especially with modal={false}) but still somewhat slow.

Possibly related: radix-ui/primitives#1634

[david-crespo]

Yeah, after commenting out nearly all the P3 color styling and still seeing the issue, I don't suspect the colors. It seems like it's just the full reflow with a bunch of divs in there taking a while.