WebGPU broken on Safari running on macOS 15 (but works on macOS 26!)

[Wumpf]

Safari 18.5 (and lower) has WebGPU as an opt-in feature. Due to a (meanwhile fixed) bug in WebKit we're always defaulting to GL device on Safari (but you can still force it) even when Safari's experimental WebGPU support is enabled.

The bug has been fixed meanwhile, see

• Investigate re_renderer failure with Safari opt-in WebGPU support #8559

I have confirmed that Rerun works fine on WebGPU in the Safari Technology Preview 223 (WebKit 20622.1.18.11.5).

We should monitor further development and enable WebGPU in new enough Safari versions once we confirmed that a stable build of Safari works with Rerun @ WebGPU.

[abey79]

As of Safari 26 running on macOS 15.6.1, I'm getting a blank screen and the following error.

[emilk]

But you have to opt-in to WebGPU on that safari version, right? Maybe that's enough to ignore that problem

[abey79]

Correct. #11292 works if you didn't opt-in. But if you did, the experience is absolutely awful: black screen and no actionable error. Also, no way out but updating the url manually to force webgl, or disable opt-in.

Weirdly, the experience is actually worse than it used to be (see #8559, there were glitches, but the viewer would otherwise run correctly).

[Wumpf]

But you have to opt-in to WebGPU on that safari version, right? Maybe that's enough to ignore that problem

Both for Safari and Firefox the reason that browser-wide opt-in will completely break Rerun is the reason we use WebGL by default on these browsers right now: the problem is that if you've opted in at some point in the past, then Rerun will just fail and you may not know why

(for Firefox it's more subtle still: we only fail if there's a video in your scene)

[Wumpf]

Bug for Safari 26 @ MacOS 15 regressing
https://bugs.webkit.org/show_bug.cgi?id=299510