They work for me on the same version of Chromium.
Could you describe what is not working?

On Firefox everything works fine.

On Chromium in a place where should be wasm sixtyfps demo apps, it's just white.

E.g. https://sixtyfps.io/releases/0.1.6/demos/slide_puzzle/

when I open Developer Console I see:

slide_puzzle_bg.wasm:0x1bbbec Uncaught (in promise) RuntimeError: unreachable
    at slide_puzzle_bg.wasm:0x1bbbec
    at slide_puzzle_bg.wasm:0x1c5dc3
    at slide_puzzle_bg.wasm:0x1c2da0
    at slide_puzzle_bg.wasm:0x3fd80
    at slide_puzzle_bg.wasm:0x90f33
    at slide_puzzle_bg.wasm:0xd4f12
    at init (slide_puzzle.js:1268:10)
$func2168	@	slide_puzzle_bg.wasm:0x1bbbec
$func2697	@	slide_puzzle_bg.wasm:0x1c5dc3
$func2496	@	slide_puzzle_bg.wasm:0x1c2da0
$func270	@	slide_puzzle_bg.wasm:0x3fd80
$func309	@	slide_puzzle_bg.wasm:0x90f33
$main	@	slide_puzzle_bg.wasm:0xd4f12
init	@	slide_puzzle.js:1268

Interresting. The exact same works for me.
And i'm also using an up-to-date Archlinux

.

Yes, I know. It works for me on Firefox on Arch Linux, and on Chromium on Ubuntu. But not on Arch Linux.

Based on stack trace , are you able to identify control flow ?

Otherwise, if you would have some debugging build with tracing information dumped to console, I am more then happy to try it out and post here results from console.

Perhaps this is a webgl related problem. What graphics card do you have? Does this demo work for you in Chrome? https://mdn.github.io/webgl-examples/tutorial/sample3/

What does https://webglreport.com/ report for your setup?

Bingo! I am getting "Unable to initialize WebGL. Your browser or machine may not support it".

Maybe good to add to sixtyfps demos/examples/templates error handling code to display error message (webgl or any other failure)?

(and also maybe good to add some fallback canvas rendering in long term?)

I agree, we should show an alert in that case.

The main() of our demo could return a Result<> instead of unwrap'ing the Slint result.
and the entry point of wasm could react to it and do an alert.

That would be very nice, indeed! I think for that to work, we need to provide an implementation of Into<JsValue> for PlatformError (at least my local attempt at doing this bails out with this requirement).

We could perhaps have a weak dependency on wasm-bindgen in i-slint-core and then implement it there, but that would imply that wasm-bindgen becomes a public dependency in our API, I guess.