I have an active 3D printing forum and I wanted to add .gcode (plain text) and .stl (3D Model format) into the forum.
Now I went ahead and set the .gcode one to a Plain Text type, selected the text gif and then Allowed it in the Extension Group.
For the .stl extension, I made it a Downloadable Files format, zip icon, and then also Allowed it in the Extension Group.
Is that the best method for the latter? It's obviously not in the pre-defined groups and was curious what others do on their boards?