I'm running Linux Ubuntu and just to confirm both those sites work fine, so it must be a problem with Mint. Are you using the the version that came with the Mint distribution rather than downloading it from the Mozilla site?
I have to say, I don't get the problem with the previous version of Linux Mint, however, that's not helping you.
Can I make a suggestion?
Open up Synaptic (your package manager) and select Opera for installation. If you're uncertain how to do that, you either scroll down until find Opera and then tick the box - "mark for installation", then click apply or use the search facility and do the same.
Opera will be automatically downloaded for you and installed. (no reboots required).
Personally, I think it's surpassing Firefox and really is a very nice browser.
This will resolve two problems. First, if it doesn't crash, it suggests the bug is in Firefox and not Mint. Second, if it works well, it gives you an alternative until such times as Firefox is fixed.
octal. Yes I am using the version of firefox that came with Mint 9.
LastChip. I have installed Opera and was able to view the sites mentioned.
I had a look at various firefox plugin properties and found that I did not have the correct permissions on some, they were listed as "root". After a quick read up on how to change this around, i reset the permissions to me and now all works well.
As a very senior user of windows in all of its unreliable guises, i would say that no one is ever so desperate and forlon that they have to return to expensive crappy old windows :) .those days have gone forever!......rejoice!..........
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