Copy wpnl_lbl.vxp from system\macros\wallpnl\ and paste it in custom side.
Drag and drop the file into Vertex and then alter the #LABEL# text size. Right click and go to properties.
You will have to re-start Vertex for the changes to take place.
The height of the text does not affect the width or height of the box around the label. The width of the box is calculated based on the number of characters in the label. The height of the box is fixed.
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