Another possible problem with Firefox, Chrome or Opera -- could be your connection speed and bandwidth.
If you have a slow connection or not very high bandwidth ... these will slow-down the ability for the browser to open 'too many' tabs.
As the major browsers draw on a lot of your network consumption.
If a browser doesn't have all the network energy it thinks it needs, it will often go to a 'grayed out' screen or 'freeze up' until the system 'catches-up'
Too many tabs or windows open -- same goes for downloading files.
The lighter-weight browsers don't require as much to run optimally.
In Xfce and Fluxbox, a light-weight browser is usually included by default.
In Gnome or KDE, you'd probably have to get one off Synaptic.
A lighter browser doesn't mean, it is less than enough to do what you need on-line.
Just that, they won't have all the extras; like add-ons, themes or extensions.
But, the browsing experience will be just as good as the 'big-time' browsers
I mainly use Firefox 3.7 or Midori in my Mint-8 Xfce desktop.
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