You can set fission.autostart = false on the about:config page to opt-out of this experiment and disable Fission.

Also, check out this option. https://support.mozilla.org/en-US/kb/performance-settings?as=u&utm_source=inproduct

https://hacks.mozilla.org/2021/05/introducing-firefox-new-site-isolation-security-architecture/

There are Firefox tools which show information about CPU and RAM. One is also called Task Manager (aka about:performance) which is in the menu bar > Tools > Browser Tools > Task Manager or the 3 bar menu (the exact location may be different on Firefox for your OS). Another is about:processes (type that in the address bar) and another about:memory.

does this process look normal? What is this "freshchat" that I can't get rid of? And why so many preallocates? can I reduce them?