The Window category includes the tools for controlling the display on screen (located in the border of the viewport).
The More tools with icon category includes tools that you do not find in toolbars when you are working with the default configuration.
The More tools without icon category contains tools for which icons do not exist. Tools from this category cannot be integrated in toolbars; however, you can define shortcut keys.
All modules are included in the Switch module category. You can define a shortcut key for each module. This is the quickest way to switch to frequently used modules.
Click the icon whose shortcut key you want to clear.
The shortcut key is displayed in the Current keys box. The Press new shortcut box is empty.