`request_repaint` panics when used from a Web Worker about egui HOT 5 OPEN

Thanks for describing the fix! I'll re-open this as a reminder to add docs, or add WorkerGlobalScope to eframe

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Interesting!

The fix could be for NeedRepaint::repaint_after to try to get the current time and on failure set repaint_time to -INF to just force a repaint asap. ctx.request_repaint_after(…) would not work properly from a web-worker though. Not sure how to handle that case.

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It's possible to get the time though, chrono::Local::now() works from the web worker. But eframe is using the Performance api which isn't exposed by js-sys for workers apparently (though the object is useable from workers). Either we could write some kind of wrapper for that that calls the Performance api without using the window object, or when called from a web worker request_repaint could use the low resolution time.

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web-sys exposes the Performance API for workers as web_sys::WorkerGlobalScope::performance. You just need to be using web-sys 0.3.65 or later and have the Performance and WorkerGlobalScope features enabled.

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web-sys exposes the Performance API for workers as web_sys::WorkerGlobalScope::performance. You just need to be using web-sys 0.3.65 or later and have the Performance and WorkerGlobalScope features enabled.

Thanks, that was it! Performance was already listed by eframe but not WorkerGlobalScope, adding it fixed the problem. I think mentioning that in the docs somewhere (for other people who'd like to use egui along with Web Workers) could be good

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