Maybe I am wrong. actually I just want to add some comment in LP today. 2 pieces of fact leads to my thoughts are 1) once I switched the theme from Tropical to built-in ubuntu such as clear look, the open dialog populates its content fast and cpu consumption is quite low. 2) this didn't happen before but I can't recall the exact time. On 2009-12-22 and 2010-1-28, there were two upgrades, one is 1.5.1 and another is 1.5.2. I noticed the problem around middle of Jan this year.. But it's likely you're right. Maybe I miss some configuration for gtk. If anyone can suggest what configuration file I shall provide, I'll be happy to post here. Still, if it's just because of config missing, shall some improvement to avoid stucking in the "Open File" dialog? 2010/2/23 François Vogelweith