You can find the current multi-process state on the Troubleshooting Information page (about:support). *"Help -> Troubleshooting Information"<br>"Application Basics":<be>Multiprocess Windows and Fission Windows<br>"Remote Processes" (Web Content) You can check the <b>about:memory</b> and <b>about:processes</b> pages for info about all processes. There are several <b>toolkit.aboutProcesses</b> prefs on the <b>about:config</b> page to show more info. See also the <b>about:unloads</b> page for info about the tabs. *https://Firefox-source-docs.mozilla.org/browser/tabunloader/ You can possibly modify this pref on the <b>about:config</b> page. *about:config => dom.ipc.processCount.webIsolated => 1 *https://support.mozilla.org/en-US/kb/about-config-editor-firefox

You can try an extension like [https://addons.mozilla.org/en-US/firefox/addon/auto-tab-discard/ Auto Tab Discard].