Having installed a fresh copy of Slackware64 13.37, I’ve noticed the following Firefox 4 quirks:
1. Firefox no longer offers to save your tabs when you click to close it.
To restore the feature you need to change the browser.showQuitWarning value to ‘true.’
2. The useragent option can’t be set in the config.
To set the useragent you need to create a new string in about:config
general.useragent.override
and assign it a value of your choice. In my case it looks as follows:
Mozilla/5.0 (X11; Linux x86_64; rv:2.0.1) Gecko/20100101 Firefox/4.0.1/Slackware
Update [27/07/2012]:
Now I’m running Firefox 14.0.1 and the useragent string should be as follows:
Mozilla/5.0 (X11; Slackware; Linux x86_64; rv:14.0) Gecko/20100101 Firefox/14.0.1