Only Firefox running in background

If you run with native Wayland (MOZ_ENABLE_WAYLAND=1), it will avoid rendering occluded windows.

Nothing has changed formally In fact, the processor fan stopped turning on, which means that part of the load was turned off. This is a good step in the right direction. Anything else I can do? That do you think about "safe mode"?

You can try Firefox from the official Mozilla server if you currently use a version from the repositories of your Linux distribution to see if it behaves differently.

• https://www.mozilla.org/en-US/firefox/all/#product-desktop-release

You can create a new profile as a quick test to see if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles

If the new profile works, you can transfer files from a previously used profile to the new profile, but be careful not to copy corrupted files to avoid carrying over problems.

• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

Open Firefox Task Manager (Shift+Esc) to see the processes using CPU. You can also show threads by changing toolkit.aboutProcesses.showThreads to true in about:config. Record a performance profile to get even more details and a sharable link.

Using Wayland really help to decrease processor load. But there are number of processes working in background. I do not need it. Absolutely. How to disable any activity on inactive tabs and unfocused windows?

Hello

For information purposes https://connect.mozilla.org/t5/discussions/why-so-many/td-p/38129

https://connect.mozilla.org/t5/discussions/121-0-1-useless-quot-xyz-is-slowing-down-firefox-quot-links-stop/m-p/49414/highlight/true#M17683

Does anyone know a working browser that does not load the processor with a bunch of background tasks and supports some kind of adblock? Opera?

Close processes in about:processes (Shift+Esc) to free up memory.

Reduce the number of processes per site by changing dom.ipc.processCount.webIsolated to 1 in about:config.

Unload tabs automatically by changing browser.tabs.unloadOnLowMemory to true in about:config and increase browser.low_commit_space_threshold_percent to make it more aggressive.

Install an extension like Offline when Minimized or Auto Tab Discard.

Have a look at this extension.

https://addons.mozilla.org/firefox/addon/auto-tab-discard/