Binary mask to choose which mouse buttons this button will respond to. To allow both left-click and right-click, set this to 3, because it's BUTTON_MASK_LEFT | BUTTON_MASK_RIGHT.
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Binary mask to choose which mouse buttons this button will respond to. To allow both left-click and right-click, set this to 3, because it's BUTTON_MASK_LEFT | BUTTON_MASK_RIGHT.