Clicking and dragging on an XML GUI button hides the image#343

1. Create XML GUI button with image.
2. Click mouse on button, but drag mouse off button.
3. Release mouse elsewhere.
4. Note that the image is now invisible until the mouse is clicked again.

Tiny XML GUI to reproduce (create an image called “hex_image” first):

<Panel allowDragging="false" returnToOriginalPositionWhenReleased="False" raycastTarget="false" >

<Button width="150" height="130" fontSize="32" textColor="#FFFFFF" colors="#FFFFFFFF|#EEEEEEEE|#FFFFFFFF|#FFFFFFFF" image="hex_image" >
Test
</Button>

</Panel>