BREAKING CHANGE: With 26.x support dropped, I've dropped:
- doom-plist-delete: use map-delete instead
- plist-delete!: use cl-callf + map-delete instead
- doplist: use (cl-loop for X on PLIST by #'cddr ...) instead
These were removed as part of an ongoing effort to eliminate
redundancies with built-in packages and reduce Doom's overall footprint.