I can’t attach a text or RTF file to a card in Trello, it says unsupported format.

[John Roach]

It seems like a no brainer apparently not.  Where’s the love for basic text.  

[marc -Collabello--Phase Locked-]

Hi @John Roach.

if attaching does not work, you can at least use a link to such a file format (I know, this is not as good).