Steps to reproduce:
- Go to https://en.wikipedia.org/w/index.php?title=Special:NewPages&namespace=2
- Note that "User" namespace is selected.
- Click "Hide bots".
Expected: The namespace is still "User".
Actual: It changed to "Talk".
This also happens for any other namespace except "(Article)" and "Talk".
From a quick glance, https://gerrit.wikimedia.org/r/340775 looks suspicious.