Oh, the underscore of menu items is something completely different, and goes back to DOS or better said Win 3.1 times, where you could navigate through a menu by typing in the first letter of the menu item while you are in the text menu. Many software still behaves this way. But this is not the official shortcut for the tool. Just a navigation convenience for text menus. It expands the sub menus.
And the scale behaviour in Bforartists is a bit different. But behaves the same in the end. You need to keep the mouse hold down. Then you can type in a value like in Blender. When you release the mouse then you are out of the mode. This wasn’t technically to solve in another way, sorry. But you get used to it 🙂
So press R, hold down the mouse to scale, type in your axis, X for example, then the value that you want to use. Or move the mouse to scale along the chosen axis.
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