Not just every launch, but also if you leave it long enough, it'll pop up again during the same session. This was what made me finally uninstall it.

And while Firefox has lots of flags and ways to tweak things like this, it's not straightforward and requires time to interrupt my workflow to address. Definitely not worth it for me on macOS. I might change my tune if I switch to Linux, but at that point I'll likely look into something like LibreWolf.