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Multiple Instances of Firefox Running in Task Manager

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Hello, Every time I open Firefox and use just one tab, up to 15 additional instances of Firefox show up running and taking up memory resources in the Task Manager. I know this should not happen. Can you please advise on how I can restrict the number of additional Firefox tabs. I already tried going into the Preferences using about:config and changing the auto.tab to false but that didn't work. can you please provide instructions on how to restrict so many instances of firefox running at the same time. Thank you. Tom Rogers

Hello, Every time I open Firefox and use just one tab, up to 15 additional instances of Firefox show up running and taking up memory resources in the Task Manager. I know this should not happen. Can you please advise on how I can restrict the number of additional Firefox tabs. I already tried going into the Preferences using about:config and changing the auto.tab to false but that didn't work. can you please provide instructions on how to restrict so many instances of firefox running at the same time. Thank you. Tom Rogers
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Here's info on the processes. In the article it also shows how to disable it.

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

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

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