These days X.Org & Co. are slowly dragging me to the end of my patience. A short list of problems:
1.Configuring the laptop touchpad. Currently there are no tools to easily configure the touchpad. GSynaptics has incomplete support and the configuration is lost after Xorg restart. KSynaptics doesn’t work anymore because it expects some shared memory, which cannot be enabled whatever you do in Xorg. Go deeper to ugliness of HAL rules, you’ll do it, in hours.
2.XKB only accepts 4 keyboard layouts at a time (FOUR). A stupid small number, chosen by fair dice roll. Good that the dice didn’t say 1. It was known and discussed at least since 2005: http://community.livejournal.com/xkbconfig/304.html (When I write this is 2009, FTR). KXKB of KDE 3 protected me from this, the one from KDE 4 doesn’t.
3.X.Org turns of external monitor output, for good. Video projector at presentations, that is. This one has been with Debian and Fedora on all 3 laptops I touched for at least 9 months (graphics from Ati, NVidia and Intel). You need to have the external monitor plugged in at computer startup so that it doesn’t get turned off. It may be gone with the current X.Org from Debian unstable, as it fixed other bunch of stuff too. It really gives you confidence when giving presentations (and makes you look professional when audience sees terminals scolling 
)
I forgot the rest, X.Org has had other limitations known for long which didn’t really hit me, ex.: cursore movement is lost at screen edge, affecting game developers; total number of keyboard key codes is limited (can’t use some special buttons on keyboard); problems with programs taking cursor focus for good, taking the whole screen for good; clipboard problems continue to exit (maybe 100% application toolkit problem). This is totaly from memory and I may have to stand corrected very easily.
4.Video drivers. Word of mouth says that everyone except NVidia has big problems on Linux. I know it’s true for Ati, FGLRX seems to work without crash only for a minority, I have no hope to see performance from Radeon/Radeonhd. It’s been very low when I first saw Linux 5 years ago, it’s the same today. Playing with 3D modelling tools is less and less fun.
5.ALSA – integrated speakers never mute, specific to some laptops. I didn’t see any help from any developer for half a year (https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4165 + plus bugs at Debian and RedHat). Yes, I looked at ALSA drivers code. I may have to say I’m not smart enough to solve this without days of looking through code. And the lack of *any* suggestion made me feel extremelly frustrated, after begging for attention times in a row.
I have to thank KDE developes for making wonderfull programs available for other platforms, to make the possible transition less painfull. I won’t have KWin and middle click paste for example, but who knows, maybe these will get solved.
If anyone may be asking how I help: I took the time to report and try to provide steps for lots of bugs (>50 at Debian, tens at KDE and some in other places) and then follow them, these days I actually worked on some KDE stuff and I hope to come with more patches.
I actually looked at ALSA and X.Org code, but it may be that I’m not smart enough for that.
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