I upgraded one of my blogs to WP 2.1 and in the process I ran into an interesting problem. When I tried the insert image button I could not see the insert or cancel buttons at the bottom of the pop up window. When I clicked on X to close the window, it refused to close. This problem only occurred in Firefox 2.0.0.1. It did not occur in Internet Explorer. It also failed when I used Firefox and tried to view the page using the IE tab add-on.
This morning I decided to try the portable version I have of Firefox(2.0.0.1) and it worked. So I went back to my desktop version of Firefox and cleared the cache(Options – Advanced). Now it works.
I think this problem occurred when I tried to delete some directories during the upgrade and I did not notice that they did not go away before proceeding with the rest of the install. When I moved the new directories into place I got a mixture of new and old code rather than a clean install of new code. During my initial testing I noticed some problems and replaced the directories a second time.
I am guessing that an old version of the javascript was still in the cache for my desktop Firefox. The browsers that worked had the correct version.
REMINDER TO MYSELF — Be patient! Rename the existing directories before installing. You can delete the old directories after everything is working.