Work in Progress.
On this page, various KDE Tips & Tricks to help make those most annoying glitches work properly.
First of all. Ever noticed how when you have Konqueror open, and you open up, what you'd hoped to have been a file manager konqueror, and it spawned up in a new tab of the browser konqueror? Well, let me explain to you about Konqueror profiles, first of all. Konqueror lets you define and save various "profiles" to which it allows different behaviors, toolbars, panes, etc. If you're using Konqueror as a Web Browser now, go up to Settings. See the second entry now, Save View 'Kubuntu Web Browser'? That's because Konqueror was loaded using the 'webbrowser' profile. There is a similar profile to that, 'Kubuntu File Manager', or 'filemanagement' as the literal name.
Now, lets get to how this actually does any good to correcting the filemanager vs webbrowser issue. Lets start with the association. In kcontrol, or a Konqueror window, I'll go with the shorter route, and go through the konqueror window. Click on Settings->Configure Konqueror, then go to File Associations.
Normally, files/directories use a mime type of inode/directory, so lets expans out inode, and click on directory inside there. Do you have Konqueror as the Application Preference Order? Now lets edit that entry and switch to the Applocation tab there, so we can fix that up a bit. First of all, lets call is what it really is supposed to be. Replace Konqueror with File Manager, or whatever you like really.
What you probably see for the Command is something like:
kfmclient openUrl %u inode/directory
What we need to change it to is:
kfmclient openProfile filemanagement %u
Voila.. This makes all inode/directory-based mime-types specifically use the filemanagement konqueror profile for your user.
Want to do this globally for all users? That's even easier, now that we know what it is we needed to look for. You'll need to do this as root, so lets do:
sudo nano -w /usr/share/applications/kde/kfmclient_dir.desktop
In this file you should see, not too far down, Exec=kfmclient openURL %u inode/directory., lets change that just like we did before, to kfmclient openProfile filemanagement %u and now it'll work globally.. At least until you update KDE again.