After installing kdenetwork and Samba and trying to share a folder via right-click -> Properties -> Share and activating "Share this folder...", the folder cannot be connected to from other devices. Also, when enabling "Allow Guests" and making adjustments there, these settings are never saved, i.e. the next time the dialog is invoked, they are reset to defaults ("Allow Guests" is unchecked).
Do you have the samba-common package installed?
Hi, yes: > samba-common is already the newest version (2:4.7.6+dfsg~ubuntu-0ubuntu2.13). I also didn't see any changes to smb.conf (I would expect that sharing a folder would write these shares to smb.conf?). I've now added the desired folders manually there, and sharing works. However, I would of course expect the GUI approach to work as well... (the path that I wanted to share is /db, which is a folder on the same partition as the root filesystem, and contains my "stuff"). Let me know if you need any more info.
(btw, when I tried to connect to the share after adding it via the GUI only, I got "Incorrect username or password" from the iOS "Files" app. Maybe the GUI does not add the corresponding user to smbpasswd?)
Ah yes, sill me for forgetting that! That is the exact issue. You've gotta do that by hand until Bug 334875 gets fixed. *** This bug has been marked as a duplicate of bug 334875 ***