Not sure if it’s something with my account or an incompatibility, but when I look in the Sent folder in crossbox, it only contains items sent via crossbox (none of my historic messages or any sent from another device). I’ve also noticed that after sending messages via crossbox, those sent messages are appearing in my Inbox when I check in Roundcube or Mail on iOS.
I didn’t see any settings that looked like they’d affect the way the Sent folder was configured, is there a way to correct this?