[alchemio]

Flash apps and Java applets (via Cheerp) can run again in browsers thanks to wasm.

[MaxBarraclough]

I imagine this would be possible with just JavaScript. It would probably run somewhat slower than WASM, but still, it's possible to transpile Rust to JavaScript. [0]

[0] https://en.wikipedia.org/wiki/Asm.js#Programming_languages

[Alifatisk]

If it's a little Java application, you can also port it to Dart, they share a lot of similarities. I did this and it was quite easy, but in my case, it was a little javafx application that drew to the canvas, not many dependencies where used.