Problem: multiple possible containers exist in that place. Eg a leaf panel and several ancestor stacks. And the program does not know in which container the user wants to drop. It is one of reasons why in LA it isn't drag-drop. Other apps display multiple indicators (for multiple possible containers), but then it becomes confusing, sometimes limited, and not better than the LA's way.
Toolbar height: it is made maximally flexible. Eg a stack can contain child panels and toolbars.
Toolbar height: it is made maximally flexible. Eg a stack can contain child panels and toolbars.
Quote:I am no longer able to change the height of the menu barThe splitter between the toolbar rows is just 1-pixel width. Can't find it? Maybe it becomes 0 width in certain DPI, but unlikely.

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