After upgrading to Firefox 2.0 I noticed that not all my tabs were showing at the top. I had to scroll right and left or select from the dropdown list. I personally would rather see all my tabs on the same bar even if they are really short. I opened a new tab, typed about:config and found the parameter browser.tabs.tabMinWidth and set it to 20. It defaults to 100. Much better.
Upon upgrading to the Firefox 1.5 1 beta release many of my extensions did not work. Not knowing why I did a few searches. After just what seemed like nanoseconds I found an article on Roachfiend.com that outlined a simple fix and an helped me understand how firefox extensions work.
By simply changing the child node inside install.rdf to 1.5 (the 1.5 beta version) my pagerank extension now works with 1.5. Example: < em :maxVersion>< strong>1.5< /strong>< /em>
Note: This works on extensions that have almost nothing to do with the new browser code.