Update worked, but EE still presents familiar CP lavender theme instead of cool new one with green button.
URL & path to themes folder is correct in General Configuration.
Permissions are 755 on themes and cp_themes.
Only the selection “Default” is available for Choose Control Panel Theme in My Account. Ditto in Control Panel Settings.
I note, as has been observed elsewhere, that the updating instructions do not tell you to copy the themes folder from the download to the site being updated.
That seems odd because the cp_themes folder in the download contains two folders, “classic” and “default”, while the site only contains “default”.