Swapped message use.
Fragment of a discussion from Translation UX feedback
Works for me: it expands or compacts the *editor*, is that the misunderstanding? I'm updating docs.
The messages are reversed. The "collapse" message makes the subwindow appear. The "expand" message lets the subwindow dissapear. This is the opposite ot what you would expect. Whatever is wrong, the tooltips need to be altered (imho swapped) to match editors intuitions.