I have observed many people suggesting to delete unused bookmarks, as tips to overcome slow start-up of firefox, is there any technical reason behind it?
I don't believe that bookmarks play a major role in the startup process.
Whatever you do, the startup of FF will be slow, in direct proportion to the number of add-ons. And since one of the best reasons to use FF is its wealth of add-ons, we wouldn't want to change that.
The solution is rather to never really close FF, just to get it out of the way.
I use the extension Minimize To Tray, which minimizes FF into the system tray. That way, it doesn't take valuable taskbar space, and FF is always available with a simple click on the tray icon.
Since Firefox 3.0, Firefox now uses a database (specifically,
Some of the things you can do to speed up Firefox are:
The first time I used the Vacuum Places extension, I saw a huge jump in performance, especially from the "AwesomeBar".
I have no experience with it, but there is also a Firefox Preloader program on SourceForge that is supposed to be able to help load Firefox faster. I can't guarantee it will help, though, as the project was last updated in 2005 (although Download Squad wrote about it in 2008, so who knows).