I wouldn't have noticed this, but for the fact that I decided to try out FireFox 4...
When trying to upload an image in Internet Explorer, there is no way to type in a filename in the Upload Image: field, shown below. The insertion point cursor can be put in there, but nothing can be typed. The [Browse...] button, of course, works fine.
Just because I needed to check some web work I happened to have FireFox 4 open, and I don't know why I tried, but lo and behold I could actually type something in there. After the first character FireFox just popped up a file selection dialog, where I finished typing the filename.
The field is even grayed-out in IE, whereas it's white in FireFox.
Is this forum software particularly well optimized for FireFox then?
Don't have an answer, but noted that in Firefox 3 if you try to type something in the box it just opens the browse window. You can't really type something in, it is basically the same as clicking on the Browse button.