attachments not showing up in the message

Our installation of roundcube has not been showing attachments in it's messages -- we've been using it for quite sometime, I have no idea how long it's been going on, or even if it's been going on forever, though I've not personally been having issues. I don't see this as a bug listed anywhere, unless I'm missing something -- any known issues with attachments not showing up, when they're clearly in the message? I've tested ccing mac mail and thunderbird users at the same time, with roundcube not displaying attachments. Thank you!