Remove the [Site Name] Prefix From Email Subjects
Strips the "[Your Site Name]" WordPress puts at the start of its email subjects, which looks dated and wastes space on phones.
Snippet Library
Email snippets for WordPress
Snippets for the emails WordPress sends: change the sender name and address, add a Reply-To header, send HTML email and turn off notifications you do not need. For site owners who want their messages to arrive and look right.