Before the update to 1.30.0-wmf.1 you could (at least in dual tab wikis like de.wikipedia) load OWE by adding ?action=edit to an URL, even with NWE enabled. This is no longer possible:
- Enable NWE on de.wikipedia
- Go to any article.
- Append ?action=edit to the URL and submit.
Expected: You can edit with OWE (or at least, any editor opens).
Actual: A page informing you the editor is loading, though it actually isn't.
I didn't test, but this probably breaks the HotCat gadget for users with NWE enabled: This creates a form with the changes the user made and submits it to action=edit, simulating a click on the "Show changes" button. (See createCommitForm in https://commons.wikimedia.org/w/index.php?title=MediaWiki:Gadget-HotCat.js).
Probably related: T165010: VE tab missing from Special:WhatLinksHere etc.