Unable to drag & drop favorite into new branch

I've created a new branch (folder) in my favorites, and would like to rearrange existing favorites into that new branch. However, I cannot seem to just drag & drop the favorite over the branch, I get that red stroked circle mouse icon then. What's the correct way to achieve this?

Are we talking about the folder tree, or Preferences / Favorites and Recent / Favorites List?

Only the latter works for rearranging favorites. (The various Edit Favorites menu items will go directly to the Preferences page. e.g. Right-click the root Favorites item in the folder tree.)

The latter, but I still cannot add favorites to a branch. I can rearrange their order on the first level, though.

Drag them below the branch, not on top of it, and it should work.

Ah, now that I tried it again, that indeed works. But you have to drag it to very close below the branch name. If you move a few pixels further down, the favorite is moved to after the branch, not inside it, without any visual indication from the mouse cursor. May I suggest to change the behavior so that dragging onto a branch moves a favorite into that branch, and dragging to after the branch just moves it to after the branch at the same level?