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When this option is enabled you can zoom in our out with your mouse even if the mouse pointer is not directly inside the editor's canvas. To disable this mode, remove the checkmark.
Relationship Editor
--->>Here you can find entries to control the size of the circular icons in the “Relationship Editor”. The values can be adjusted for node icons and the hub symbol separately.
Node shape radius
Define the radius of a node icon in pixels.
Hub shape radius
Define the radius of a hub icon in pixels.