There appears to be a bug in the more recent flash player which appears to break the mouse events. It only appears to affect Macs, I am having the problem on both Safari 4.0.3 and FireFox 3.5.3. I made a test app below which adds a few mouse event listeners to the white box and informs you of the events being received. Try it out below and comment on your results.

If you do not have a problem, do not upgrade your flash player or you will. This has been reported as a bug to Adobe here and here, more people are starting to notice it, hopefully Adobe will fix it soon.

Update 25/09/09

So far the results of people trying out the above test on a mac have been varied. The problem seems to be occuring in Snow Leopard 1.6, with most people FireFox being the only browser experiencing the bug. I have witnessed someone running Leopard with the same versions of FireFox and Safari as myself with no problems at all. Most people who are running Snow Leopard appear to only experience the bug in FireFox with safari working fine. However, as I mentioned above,  I am having the bug appear both in Safari and FireFox. I don’t know what is so different about my set up, apart from that I have installed the latest debugger version of the Flash Player and that my system is 32-bit only.

If you do try out the test above and want to report your results, please provide as much information as you can, what versions of browser you are using, what is your flash player version, what OS version, 32 or 64-bit etc? Some people think the problem is with FireFox but I am not so sure.

Update 06/10/09

Ok, I am pretty sure now that this problem is not to do with a flash player upgrade, it is to do with Snow Leopard!

Recently my hard disk died, I reinstalled Snow Leopard and then restored my files from a time machine backup, I did not restore my applications.

Upon reinstalling Flex Builder I noticed that my flash player was now at version 9, which gave me an opportunity to test if this bug was still happening and it is, both in Safari and FireFox for Flash Player 9,0,124,0 as well. This almost definitely means the problem is down to the operating system, either Apple needs to fix it or Adobe need to come up with a fix in Flash Player. I can not run my demo test app above using flash 9 as the demo is set to require 10, but in other test apps I am getting the same broken behaviour with mouse events being lost after loading the FileReference browser. Looks like we will need to put a warning for Snow Leopard users on our flash apps.

Update 22/11/09

Adobe Labs have recently released Flash Player 10.1, which has fixed the issue detailed above. I have tried out the new player, but while the problems above have been fixed, many others new problems are present. For example, it appears that key events are duplicated, every keystroke entered appears twice and filtering by file type does not appear to work with FileReference. I realise this is a pre-release version constantly being improved, so hopefully these will be fixed soon. Unfortunately there is no debugger version of the new player, which is quite strange since the people who are going most likely to try out a pre-release are developers who would require the debugging features.

So far it appears I am the only one that has experienced these problems with the latest player, I think this is somehow related to my system being 32 bit only. It appears that most of the development efforts into Flash on the Mac are on 64 bit support, which makes sense since Apple is shifting eveything to 64 bit. If you too try out the new beta flash player and experience other bugs please report them here and on the adobe bug reporting site. This new flash player update proves that an active Flash community can get flash bugs fixed quicker and help improve the flash platform for all. Thanks to all who commented on their issues experienced with the demo.

You can try out the new 10.1 player at the Adobe Labs site.