Users reported that pinch zooming on iOS (specifically 18.2) caused crashes, particularly when zooming into content and then swiping or zooming out aggressively tvavrda. While some users couldn’t reproduce the issue on iOS 18.2.1 david, tvavrda confirmed it persisted under certain conditions. The team reproduced the issue and identified it as likely a browser bug, but implemented a fix in Discourse core sam. However, crashes continued in the Graceful theme, prompting investigation into potential z-index issues sam. A fix was submitted and merged for the Graceful theme pmusaraj, which tvavrda confirmed resolved the issue. Later, pinch zoom stopped working entirely in PWA mode tvavrda, which was traced to a separate regression affecting DiscourseHub/PWA, not Safari pmusaraj. A follow-up commit resolved the PWA zoom issue david, and tvavrda confirmed functionality restored. The root cause is suspected to be a recent Safari regression, though reproduction outside Discourse remains elusive pmusaraj.
iOS 18.2 pinch zooming mostly crashes. Cannot zoom to images but also anything in a topic.
UPDATE: It seems to happen when you pinch zoom and then you “rough” swipe with one finger (e.g. to move all the way down) when zoomed in. Or zoom out. You must zoom into a content. When you zoom e.g. on buttons, it might not crash.
Crashes like this are likely browser bugs, that said I have alerted the team in case they have any ideas.
I haven’t been able to reproduce this on iOS 18.2.1.
Is anyone else seeing the same problem?
OK, I upgraded to 18.2.1 and after few tests I cannot reproduce again.
It happened again (iOS 18.2.1). If I zoom in and then I zoom out but much more than 1:1, I can reproduce the crash.
Thanks @tvavrda - a few of us on the team have been able to reproduce the same issue, and are looking into it 
It is certainly a browser bug, but @pmusaraj just merged a fix that appears to fix it in our testing.
https://github.com/discourse/discourse/commit/73b28815e301e26c7f4a0a449e205487c4e9d6bc
Can you confirm all is working after you update?
It works now on the default theme. But I have GitHub - discourse/graceful · GitHub installed and there it still crashes 
@pmusaraj / @awesomerobot I wonder if graceful has some elements with -1 z-index?
It does but removing it did not help. Or maybe I did something wrong.
We will have a look will keep the bug open for now.
(I tagged it for clarity on what the bug has evolved to)
This should fix it: FIX: Prevent bug with pinch zooming in Safari iOS by pmusaraj · Pull Request #40 · discourse/graceful · GitHub
I’m going to file this upstream tomorrow (or see if somebody else filed it), this very much feels like a recent regression in Safari on iOS, this code has been in the Graceful theme for a long time.
The fix above is now merged, looks good here on meta, hope it’s the same on your instance @tvavrda, thanks for the report!
I tried to repro this on a simple codepen so I could report upstream, but I can’t repro. Something else on our app might contribute to the problem, trouble is, not sure how to track down what else is a contributing factor.
Seems good so far! I had a customized theme so I just reproduced your modifications and it looks good. I can finally look at images from my phone! Thanks for the support 
Pinch zooming stopped working whatsoever to me now 
Yes, confirmed, must be a different regression. Looking into it!
@tvavrda are you testing on Safari for iOS? Here on meta, I can pinch zoom in Safari, but I can’t in DiscourseHub (our mobile app).
I am on iOS 18.2.0 (upgrading to 18.2.1 and testing again).
You are right. It works in the browser. I use PWA. There it doesn’t.
Sorry about that! I hadn’t specifically tested DiscourseHub/PWA with one of my recent changes. This commit should fix up pinch-zooming there.
Seems to work again on PWA. Thanks!