I’m writing this because I’ve spent about 5 hours trying to resolve this without luck until finally, I hit gold. This is a new install, a week old, using the newest KDE version with all updates installed. BTW, I love the Fedora sweet-spot of stability along with recent packages.
I did a lot of straces, went down many rabbit holes, but couldn’t stop dolphin hanging for 8 seconds before being responsive in any way (even closing the window).
I have fuser mounts running, Google Drive and sshfs to other machines including my Synology NAS using systemd so I was chasing down those. Edited the service files. No change.
Changed every setting in Dolphin that might have it looking at places or remotes. No change.
Did all sorts of diagnostics with kio-fuse, kio-worker, dbus monitoring, xdg-document-portal stale fuse mounts, clearing caches, restricting file searches, checking suspect services, tracking down file descriptors and sockets, disabling the network, session manager communication, virtualbox shared folder, /etc/hosts file, bad user-dirs.dirs directory, font cache corruption
Finally I ran Dolphin with QT_LOGGING_RULES="*.debug=true", I saw a specific error message:
QT_LOGGING_RULES="*.debug=true" dolphin 2>&1 | grep -i "kio"
> kf.kio.core: We got some errors while running testparm "Weak crypto is allowed..."
This proved that KIO (KDE’s input/output architecture) was calling testparm to check security settings. Because the Samba config was “ambiguous” or “legacy,” the check triggered a GnuTLS security timeout.
After some Googling, it seems Fedora has moved to stricter crypto policies than on my previous installs. The standard min protocol = SMB2 is now considered too broad/weak by the system’s libraries. The fix was to explicitly define SMB2_10 and forcing ntlmv2-only or disabled satisfies the security check instantly, allowing the KIO worker to finish and the Dolphin UI to populate.
client min protocol = SMB2_10
server min protocol = SMB2_10
client ipc min protocol = SMB2_10
ntlm auth = ntlmv2-only
This was likely my error moving my smb.conf file froma previous installation of MX or Mint. I hope someone finds this useful.