[jeroenhd]

Definitely possible, especially with native-to-WASM tooling.

I've used a web page to run ADB commands to quickly debloat my phone, so I don't see why fastboot support wouldn't work.

There's even a tool to flash your Android phone through the browser (https://pixelrepair.withgoogle.com/ I believe). Adding "automated LineageOS installer through WebUSB" to my infinitely growing to-do list :)

[intelVISA]

That sounds great, I hope you pursue it.

Do you know of any specific risks when flashing devices w/ WebUSB as opposed to the 'normal' way?

[mschuster91]

With Google's devices I think and hope that the code accounts both on the web side and the device firmware side for interrupted communications or latency due to whatever external factors (e.g. another page that is running in the same execution context sending the single JS thread into a loop or lock).

With non-Google devices... these might run into problems when the device expects a certain response latency or minimum bandwidth. YMMV I'd say.