Can you post a pic of the Task Manager Performance tab please? Just curious...

FISSION: The links are sites explaining the Firefox's Project Fission. Users are complaining about ram usage, but this is the reason for the processes you see in task manager. You can turn fission off by setting it to false on the about:config page. see screenshot Here is more info. https://www.ghacks.net/2016/02/15/change-how-many-processes-multi-process-firefox-uses/

Introducing Firefox’s new Site Isolation Security Architecture https://hacks.mozilla.org/2021/05/introducing-firefox-new-site-isolation-security-architecture/

Firefox's Project Fission: better security and more processes https://www.ghacks.net/2019/02/07/firefoxs-project-fission-better-security-and-more-processes/

Visit about:processes in the address bar (Shift+Esc) to get more details.

It is quite normal to see more Firefox processes running.

• process for the main Firefox thread (user interface)
• one or more content processes
  you see more content processes when Fission is enabled
• process for the compositor thread
• process for extensions
• process for WebRender when this feature is enabled

You can find the current multi-process state on the Troubleshooting Information page (about:support).

• "Help -> Troubleshooting Information"
  "Application Basics":<be>Multiprocess Windows and Fission Windows
  "Remote Processes" (Web Content)

You can check the about:memory and about:processes pages for info about all processes. There are several toolkit.aboutProcesses prefs on the about:config page to show more info. See also the about:unloads page for info about the tabs.

• https://Firefox-source-docs.mozilla.org/browser/tabunloader/