I could make out that there was a lot of Read (I/O) operation happening when Firefox starts and also the RAM took a big hit. So I could narrow it down to be some faulty add-on that must have been playing the trick. So, I went ahead and opened the options and began hacking a few settings.
Opened the Tools > Options > Privacy. Change the drop down to "Use Custom Settings for History" and then you will find the culprit sitting quietly over there. There is a default setting in Firefox to remember history for 90 days which is really huge. This basically means that Firefox will be remembering each and every site you have been visited with the details such as date and time of the visit for the last three months that you have been using Firefox!!!. This will be really very very huge if you are a power user like me who spends considerable time online.
Well, to fix the slowness of your Firefox is to
simply goto the Privacy tab (Tools > Options > Privacy) and changing the drop down to "Use Custom Settings for History" and then change the setting to a much smaller value say 5 days!!Then head over to Tools >> Clear recent history and select "Everything" in the drop down and hit Ok. Once that is done - close and open Firefox to see so much of speed!!
Hope this tip helped you in making Firefox work much faster.
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