help building for mobile

HI!

I'm new here, I loved this work, an amazing work, very thanks to produce this.
But I'm facing some problems and I need some help, I tried my best.
I'm trying to run this for mobile, latest chrome, I got the next error:
`Uncaught (in promise) RangeError: WebAssembly.Memory(): could not allocate memory`
I searched here, I must build the `ffmpeg` with 0.5 GB or less.
I did, after facing problems and hours.

Then I got this error:
`Uncaught (in promise) RuntimeError: abort(Assertion failed: Cannot call unknown function proxy_main, make sure it is exported). Build with -s ASSERTIONS=1 for more info`
Searched, I must replace `proxy_main` with `main`, I did

And finally worked!
But what? After selecting the audio, the browser freeze!
I opened console, got this:
`[fferr] Blocking on the main thread is very dangerous, see https://emscripten.org/docs/porting/pthreads.html#blocking-on-the-main-browser-thread`

Now... what?
The build process takes 2 hours to end, this happens with `-s INITIAL_MEMORY=268435456` ~= 256MB of ram.
Is 256MB is the reason?
Or what can i do?

And if anyone built this for mobile and worked, can I get the built?

Thanks, and thanks for reading