• Fix the free space in a Workspace tabset's tab list (returned by useTabListFreeSpace and getTabListFreeSpace, reported to subscribeToTabListFreeSpace listeners, and set as the --tab-list-free-space custom property) not changing once the tab list is squeezed to 0px, e.g. beside a toolbar that doesn't shrink. It now keeps going down as the header's content overflows the header, and is updated when the header or its toolbar changes size.
• Fix Workspace interactions in right-to-left layouts (e.g. within dir="rtl"): dragging a tab within its tab list inserts it where it's dropped, arrow keys move focus to the tab on that side (ArrowLeft moves to the next tab), and dropping a tab or tabset onto the left or right edge of a tabset puts it on that side of the screen. The left and right regions passed to moveTab and moveTabset are sides of the screen too. A tab list's data-overflow-start and data-overflow-end attributes are also set correctly while it's scrolled. - #791