Button disappears when text is blank, even if there's a JSON image

Using version 2.536. When I use AppleScript in a Touch Bar icon, and it returns a null string "", the icon disappears as well. If I return a space " ", the icon shows up again (with a space after it, obviously). This is true even if a JSON strong is used that returns a null text value and a an icon.

Desired behavior is to display the icon when the return value is null (i.e., when no text is displayed).

Sample code:
set fileName to "/Applications/Spotify.app/Contents/Resources/icon.icns"
return "{"text":"" & "" & "", "icon_path":"" & (POSIX path of fileName as text) & "" }"

Should return just the Spotify icon, but instead, the button disappears entirely. Tried setting the width & height to 22px, but that doesn't fix it.

This is currently by design (may be changed in the future though).
To get a icon-only button currently your only option is to check this option: