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Nope this is a system level feature in Android where services can constantly run on the background.

Settings > Battery > Background activity manager

Find it in the list and switch it off.

I'm running Android 8.1.0 so YMMV

Uninstall and use chrome version.

On some phones, Facebook comes preinstalled as a system-level app that cannot be uninstalled.

Idk what to recommend other than getting a phone that doesn't do that to you.

On my phone, I never logged in to Facebook through the app and deactivated it and use the website, I hope it's sufficient.