You use Firefox and/or Thunderbird, and you get a list of dictionaries with plenty of useless entries: here's how to remove them.
For once, an article on Windows.
You are using a webmail (Gmail, Yahoo ...) and also applications or documents including mailto links, so, you would like the links to open Firefox or Chrome on your webmail: follow the guide !
To develop web site, you might want to add plugins to Firefox browser.
You want to run a Java application in your web browser Firefox (typically a webinar), you need a Java plugin installed ! Here's how to do it, in Ubuntu 12.04.
Web browsers Internet Explorer and Firefox do not manage the box model the same way.