tty2web freeze on input

[ep4sh]

What version of tty2web are you using (tty2web --version)?

v3.0.3

What operating system and browser are you using?

client os: arch client browser: firefox

What did you do?

input the a single letter like "aaaaaaaaaaaaaaaaaaaaa"

What did you expect to see?

no freezes

What did you see instead?

tty2web freezes on input randomly.

I've tried to play with buffer size (https://github.com/kost/tty2web/blob/master/webtty/webtty.go#L28) but with no luck. Have you ever faced the save issue? How to debug it?