I have recently installed Calibre, and it works great, however I have some problems with handling of files by this program: Folders open in baobab. To open folder I just need to click on a book and then select: Path:    Click to open. CBR files open in print-preview. Gobal file associations are sensible (I have checked ~HOME/.config/mimeapps.list) and cbr files open properly in nautilus. So questions are: How does Calibre detect file associations. How to change those associations. I use i3 window manager. 
How to change programs used to handle files in Calibre in Debian
debian;file opening;calibre