[SOLVED] Gnome 3.4 / GTK / Firefox freezes

Question

For the past week or so, I've been having a problem with Gnome Shell and/or particular applications freezing for around 30 seconds to a minute at a time.
I can't quite pin down what the underlying problem is. It affects Firefox most obviously: any attempt to right click for context menu, or to use the back arrow on the task bar, causes Firefox to freeze. However, it is not restricted to Firefox: I've had similar freezes affecting other GTK apps (e.g. Gnome Terminal) or even the entire desktop. The problem is affecting all users. Occasionally I am also getting a "sad computer" black screen of death when logging in to a Gnome session, but I can't tell if that's related.
I've tried downgrading the kernel to linux-lts, but that makes no difference.
Basically this is rendering the computer almost unusable, or at least deeply painful and annoying to use.
System details (if any other information would be useful then please let me know):
$ lspci | grep VGA
01:00.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Manhattan [Mobility Radeon HD 5430 Series]
$ uname -a
Linux arch-desktop 3.3.6-1-ARCH #1 SMP PREEMPT Sun May 13 10:52:32 CEST 2012 x86_64 GNU/Linux
I'm using the open source radeon driver. All packages are up to date.
Last edited by john_h (2012-05-19 18:16:54)

Answer 1

john_h wrote:I may be confusing correlation with causation , but the problem hasn't recurred since I removed this extension.
Well good for you
I've really been trying to make gnome shell a pleasant usable experience for myself, but I'm having these lockup issues frequently upon log in.  It may be due to the fact that I'm using fglrx graphics but I still don't think that should be an excuse.  I tried removing the extension and the correlation appeared to have less freezes - but I'm still in a bad position.