For most users, Firefox's hiding the "http://" prefix and the trailing slash of Web site addresses in its URL bar falls somewhere between a non-issue and preferred. (By default, for example, Firefox displays howto.cnet.com instead of http://howto.cnet.com/.) These users get a cleaner view of the Web site they are visiting and go about their day.
If you make it a regular practice to enter your own characters after the the trailing slash, however, then you can tell Firefox to stop trimming URLs in such a manner. Here's how:
Step 1: Type in about:config in Firefox's URL bar.
Step 2: Click the button promising to be careful when changing advanced settings.
Step 2: Search for: browser.urlbar.trimURLs
Step 3: Double click the line for your search query to turn the value to false.
Now, without needing to restart Firefox, you'll see full URLs for all of your current tabs and all subsequent pages you visit.