FoldingText Document Icon when set as Default

Hi there,

I’ve set FoldingText to be the default application for .txt files and .md files. I’d like them to display the FoldingText Document Icon, but it appears to be the case that only .fts have that honour. Attempting to make a change to Info.plist doesn’t work – probably because of code signing. Is there a straightforward way to make these files carry the appropriate icon? Thanks in advance!