Hm, no post expand/collapse images showing up under Linux (using Ubuntu 8.04). Error from Firefox's console that I'm guessing is related to your use of inline images:
I'm guessing something is a little different about the CSS support for Firefox 3 here.
At any rate, I can still expand/collapse posts, just don't have that pretty image.
Warning: Expected end of value for property but found '!'. Error in parsing value for property 'background-image'. Declaration dropped. Source File: <a href="http://blitzbasic.com/Community/posts.php?topic=78196" target="_blank">http://blitzbasic.com/Community/posts.php?topic=78196</a> Line: 0
I'm guessing something is a little different about the CSS support for Firefox 3 here.
At any rate, I can still expand/collapse posts, just don't have that pretty image.