Updating a forum, for example from 3.3.11 or 3.3.12-RC1 to phpBB 4, the Web Push Settings module is not installed into the correct place, it's installed as its own tab. See screenshot.

Steps to reproduce:

Create a 3.3.x forum (using quickinstall in my case)

Replace all files except for config.php with the latest nightly build of phpBB4/master

Go to Install and run the update

Go to ACP and I see the screenshot below: