Have you recently updated your Firefox 3?
I did and I just found out that I was having some problems with some sites involving the captcha entry. Some important sites that I needed to log on required me to enter the correct captcha, but with the latest update from Mozilla Firefox, it gave me a hard time logging in, and as a matter of fact, not even a chance on logging in at all.
I was having some thoughts that the latest Firefox is still in beta testing, and Mozilla is just saying that it is already official, to be able to confuse users to download and install the latest Mozilla Firefox and use the internet users for the monitoring of their "beta-like" browser.
Not to mention, I have experienced some browser crashes after the update of the Mozilla Firefox 3, even slow downs are very apparent.
But I cannot ditch this good browser though at the moment, since I am using many useful plugins installed here on my Firefox, like the Google Toolbar which lets me check the PageRank of some blogs that I hope into, and some other more plugins that I have installed.
And yeah, I have developed a temporary but sure ...