Steps to replicate the issue (include links if applicable):
- Create a custom signature on en.WP containing a set of p tags
- Save it
What happens?:
The software allows the signature to be saved.
What should have happened instead?:
The software should not allow the signature to be saved, per https://www.mediawiki.org/wiki/Topic:W4sx12qy3xt2kshe
Software version (skip for WMF-hosted wikis like Wikipedia):
Other information (browser name/version, screenshots, etc.):
This appears to be a regression. Possibly related: T255324.