TYPO3 Core

On version 13 the border is gone, but accessibility did not improve, either.

This is the situation I experienced when navigating the pagetree using the "tab" key

1) The first element that gets the focus is the search box

2) pressing "tab" again you are on the "kebab" menu (Which is operable using the "Enter" key

3) The next "tabbed step" is actually ... well... hiddden! No focus is shown but you're actually on the pagetree itself - just press the "up" or "down" arrow to see that you can highlight the pages on the tree. And it can be navigated using the arrows; the pages can be selected using "enter".

4) Then pressing "tab" again you end up on the "collapse panel" button. By the way, it is not operable using enter or space or any other key

The other icons (the pages that can be created via drag and drop) are not reachable using the "tab" key. (That could be correct)