On the left sidebar, the Levels tab gives options to add (+) and remove (-) levels, as well as the option to switch between levels. You’ll notice the selected level is highlighted, other levels are made transparent. For any selected level, its 1x1m grid is shown, although this can be toggled with the ‘G’ key. You can also display all levels using the ‘L’ key, and easily switch between levels using the SHIFT + 1-9 shortcut (use ~ for the ground floor).

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