I found this support forum post but the solution provided doesn’t work.
Edit (thanks to @moreeni@lemm.ee for the Stack Exchange link):
Solution - Go to Settings -> Home -> Enable Shortcuts -> Go to a new tab -> Google will be pinned by default, hover over the Google icon -> Click on the 3 dots menu -> Unpin
https://superuser.com/questions/1541022/how-to-removed-google-from-top-bar-in-firefox
There’s a more elaborated answer down there in the thread.
This worked, thanks!
Solution: Go to Settings > Home > Enable Shortcuts > Go to a new tab > Google will be pinned by default, hover over the Google icon > Click on the 3 dots menu > Unpin