(previously: #1998 plus #1031, #1275, #1517, #1654, #1798, #1846)

All bundled themes except Twenty Twenty-Three will need to update their changelogs when they are released.

The heading IDs/anchors should be in the pattern of #Version_1.2.

See the Trac ticket list for all theme changes (the full log contains some commits that pertained to the previous release in July).

I will add drafts in separate comments below.