But it does work if the file manager and the firefox winows DO overlap.
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None of this works on a heavily-patched PCLinuxOS 2007 box with KDE 3.5.9 and Firefox 3.6.9. Because the PCLinuxOS is rather old and very far away from a vanilla install, I reckoned I should try something more modern like Linux Mint.
(e:leetee) suggested that the problem might be that the drag and drop won't be supported from the Desktop so I tried drag and drop from the File Manager on both boxes. Linux Mint worked if the windows overlapped. But, alas, the ancient PCLinuxOS box was just too old and cranky and refused to work. Thank you for all your efforts, (e:paul). I think the mystery is solved. There is no more reason for you to do anything about this. It's a combination of user error and old software.
(e:scott) - thank you for the kind words but I always fear that no matter how I try to explain stuff in Linux it is way too geeky. For example, how many average computer users know the difference between a Desktop Environment and a Window Manager? And, more importantly, does it really matter to them? People just want stuff to work. We geeks on the other hand want stuff to work our way.
When I started out with Linux, I was a KDE gui man despite liking lots of Gnome suite apps. These days I have to say that I like the newer Gnome better than the KDE 4+ desktops. But, ironically enough, I tend to prefer KDE suite apps. Go figure.
I love E17 (Enlightenment DR17). I'm sad to say that right I don't have a box that is running E17 because I've been compiling it from source lately and I just don't have time and energy to deal with that.
Any old way, again thank you for the kind words. As you can see, I can ramble on about Linux. I'm a bit of an absent-minded professor. My train of thought often makes unscheduled stops.
Excellent summary of the different players (kernel vs desktop env) in linux for the non-linux user. Well said! (You should write those up in a separate post of their own!)
(e:tinypliny) - Gnome and KDE are both desktop environments who have their own suites of apps. In a way, they are the Coke and Pepsi of Linux Desktop environments. There are others but they are the most popular.
These days gnome and kde apps play well with each other. And I've not had any problems using Gnome apps in KDE and visa-versa since 2001 or 20002.
In general terms, in Linux, you can use any Gnome or KDE app with any desktop environment (Gnome, KDE, lxde, xfce, etc), desktop shell (Enlightenment DR17 (my personal fave), etc.), or windows manager (Window Maker, fluxbox, etc.) as long as you have access to the supporting toolkit libraries. And these days, most distros have pre-compiled library binaries available. Of course, if you are geeky, you could just compile stuff even if your favie distro doesn't have libraries for ready download.
I hope that answered your question and didn't confuse you more.
Since you are explaining stuff, where exactly do Gnome and KDE stand in this hierarchy of things? Can things made for Gnome run in KDE based systems and vice versa?
(e:paul) - If you think about it Linux isn't an operating system, it's a kernel. To me that is one of Linux's greatest strengths and one of its greatest weaknesses.
Because it is an implementation of a kernel with user space api's, anyone and everyone can make their own Linux and developers aren't limited by what the other developers are doing. While both Fedora and Ubuntu are operating systems using the Linux kernel, they aren't "Linux" in the same way that MS Windows is Windows and osX is osX. A better way to look at it is that Fedora is Fedora and Ubuntu is Ubuntu, etc. But,of course, you already knew that.
On an enterprise level, the lack of standards can cause problems. That's why the Linux Standard Base :::link::: was started.
When I first used Linux in another century, cut and paste was a real problem. Even if your distro could run gnome and kde apps, you couldn't always cut and paste between them. If memory serves it was because of qt and gtk not playing together well.
Isn't it so crazy how crazy this stuff can get because of minor differences in Linux. Sadly, this is exactly why big software companies don't want to support Linux.