Bug 244120

Summary:	iOS 15.6 Some WebGL-enabled pages freeze when taking screenshots
Product:	WebKit	Reporter:	Alexander <alex>
Component:	WebGL	Assignee:	Nobody <webkit-unassigned>
Status:	RESOLVED CONFIGURATION CHANGED
Severity:	Major	CC:	dino, kbr, kkinnunen, simon.fraser, webkit-bug-importer
Priority:	P2	Keywords:	InRadar, Regression
Version:	Safari 15
Hardware:	iPhone / iPad
OS:	iOS 15

Description Alexander 2022-08-19 04:54:54 PDT

This issue is reproduced on iOS 15.6 for some Verge3D applications. E.g:

The app which crashes https://cdn.soft8soft.com/demo/blender/metaballs/metaballs.html
The app which does work https://cdn.soft8soft.com/demo/blender/spinner/spinner.html 

When taking screenshots using Side button + Volume up (iPhone 13+) or Side button + Home button (earlier iPhones) the browser freezes completely. The bug appears to be not connected with Verge3D specifically.

Comment 1 Sam Sneddon [:gsnedders] 2022-08-19 09:15:03 PDT

Looking at the stacks, seems kinda similar to bug 237674, insofar as the UI process is blocked on -[_WKWebViewPrintFormatter drawInRect:forPageAtIndex:] + 116	(_WKWebViewPrintFormatter.mm:95).

Comment 2 Radar WebKit Bug Importer 2022-08-19 09:15:17 PDT

<rdar://problem/98885447>

Comment 3 Sam Sneddon [:gsnedders] 2022-08-19 09:26:08 PDT

Far as I can tell, this doesn't reproduce on iOS 16 Beta, so I'm assuming this was fixed elsewhere.