Description of the need
The "Date format for log messages" field at /admin/config/development/logging requires entry of PHP codes, but we already have existing date/time formats at /admin/config/regional/date-time that people might prefer to use instead.

Proposed solution
Allow people to select from either an existing date format, or a custom format that is entered on the dblog settings page. A custom format entered here would be used for nothing else.
Alternatives that have been considered
- Creating an additional date format presented lots of issues, see https://github.com/backdrop/backdrop-issues/issues/4614 for the full story.
- Original issue: Allow selecting an existing date format for log messages
Recent comments
Most likely this is a problem with views_send.
Mail does not attach pdf and is sent unformatted after upgrade to php 8.1
Yes, this was solved in MIME mail: https://github.com/backdrop-contrib/mimemail/issues/52 The issue was that starting in php 8.1, you need \r\n to separate the header lines. Mimemail did...
Mail does not attach pdf and is sent unformatted after upgrade to php 8.1
Was this problem ever resolved @argiepiano? I am experiencing something similar with smtp, mailsystem, mime_mail and views_send. If I try to attach a pdf document, it gets sent but...
Mail does not attach pdf and is sent unformatted after upgrade to php 8.1