Board Thread:Support Requests - Getting Technical/@comment-31892545-20180827220000/@comment-27345308-20180828114107

User talk pages are "archived" when Message Walls get enabled, though (just like old Forum pages got archived when Special:Forum got enabled). Not uneditable, but they redirect to Message Walls when viewed via the User talk namespace. Article talkpages are still accessible and editable, but article pages don't link to them so you might want to use TalkButton to link to them in the edit dropdown.