Krusader package currently depends on mesa.

pacman -Qi krusader

Name : krusader
Version : 1.40-1
Groups : None
Packager : eric <eric@archlinux.org>
URL : http://krusader.sourceforge.net/
License :
Architecture : i686
Size : 3719107
Build Date : Thu Jul 22 10:57:29 2004 UTC
Install Date : Tue Jul 27 20:11:37 2004 UTC
Install Script : No
Provides : None
Depends On : kdebase kdelibs mesa
Required By : None
Conflicts With : None
Description : Alternative file manager for KDE resembling Midnight Commander

But mesa is not really needed. IIRC previous krusader versions didn't include this dependency too (at least I don't have any info about it in my pacman.log - mesa was installed automatically with the last krusader upgrade).

I can run krusader fine without mesa (I removed mesa with pacman -Rd mesa and I still use extra/krusader version)

Mesa provides a version of libGL library which is also provided in the standard xorg/xfree86 package. Mesa version from x package is according to my knowledge synchronized from time to time with the original library and should provide similar functionality.

Also nvidia driver overwrites x libgl version with it's own files and they work fine too with krusader.

When mesa is installed namcap will also report mesa as a dependency for (probably) all kde applications (I sent a separate email about it to Jason - it can't be solved automatically by namcap, user has to decide). So mesa should be a dependency for any package only when it is absolutely necessary.