Stockfish 10 working on only 1 core at a time I am a lichess user who would like to be able to use my 8C/16T processor to the best of my ability, and yet when I start up a chess engine only one of my cores is working on stockfish the rest are either doing very very little of just nothing at all. Why is this happening and how can I fix it?

I am using Linux (Ubuntu 18.04 LTS)

This is what I was told on lichess forums:

Both javascript.options.shared_memory and dom.postMessage.sharedArrayBuffer.withCOOP_COEP have to be set to true.

As a very new linux user... how do I actually implement this?
Those appear to be options to set in your Web browser, which is effectively the platform that LiChess runs on.  You don't mention which browser you're using…

Chrome uses multiple cores and thereby searches many more nodes per second, without any special attention.

On my Mac, Firefox uses only one core, even after entering the settings you mention (using about:config).  However, the Linux version responds well to these settings.

Obviously, a native chess engine would be more efficient still.  This wouldn't integrate with LiChess, however.