Bug 260458

Summary: Massive performance regression on STP 176
Product: WebKit Reporter: mic.gallego
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: bfulgham, simon.fraser, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: Safari Technology Preview   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Performance issue
none
screen-recording with 267085@main none

Description mic.gallego 2023-08-20 21:54:39 PDT 
Created attachment 467357 [details]
Performance issue

Hi,

I am not sure if the issue is on TP176 or earlier, but after testing one of our theme, I have near unusable performance on Safari (everything is butter smooth on other browsers). Here is the page you can play with:

https://prestige-new-version.myshopify.com/collections/all (the first time a password will be asked, enter rewblo as password, then go back to the listing page). As you scroll through the products you will experience massive lag. I am aware of the forced layout but those are unavoidable to have one of the feature we need, and it does not cause such issue on other browser nor older versions of Safari.

Thanks! :)
Comment 1 zalan 2023-08-21 08:07:33 PDT 
Created attachment 467366 [details]
screen-recording with 267085@main

I can't repro the perf issue on trunk. Will try with the most recent STP.
Comment 2 Radar WebKit Bug Importer 2023-08-27 21:55:24 PDT 
<rdar://problem/114545208>