Split dockers don't work when maximized

To split a docker I drag to the half of it, and a bit outside the window and a blue rectangle appears indicating that it will split the docker.

This happens to any docker, not only the bottom one. I think because, obviously, you cannot move the mouse outside the maximized window.
This only works if REAPER is not maximized:


I'm not sure if it is a bug, but it is inconvenient to "unmaximize"/restore the window each time you want to use that feature.
REAPER 5.23 Win x64

Split dockers don't work when maximized