SOLVED 'open book folder' does not work under KDE Plasma

[gwitt]

Recently I came across a problem to use the function "open book folder" which did not work to open my Dolphin file manager for any selected book.

First I thought it was caused by an access problem due to flatpak, snap install. But finally I realized it was based on an insuficcient association of the file type "inode" in the KDE Plasma settings.

Solution: change file type association settings to another application > apply > change back to Dolphin > Done, you should be fine now!

detailsand help can be found under: https://userbase.kde.org/System_Sett...ssociations/en

Have fun using calibre!