The biggest issue with Adobe Flash Player
Update: Looks like they
have fixed this in
Flash Player 10.1
The biggest issue with Flash Player at the moment is that there is no way to create a top-level exception handler. What this means is that there will be exceptions (errors) that you simply cannot trap in your application code, even if you put try/catch all over your code (and especially if you are using Flex's MXML). This means that
creating things like an error reporting tool are impossible for applications that run in the Flash Player (that includes AIR apps, too, not just browser apps). If you are running the debug version of the Flash Player, you will see uncaught exceptions, but the typical user is not going to be running the debug version. In the regular version of the Flash Player, uncaught exceptions just fail silently (often causing strange behavior), giving no indication to the user that an error occurred.
There is an issue in Adobe's issue tracker for this:
http://bugs.adobe.com/jira/browse/FP-444
It is the highest-voted issue specifically for the Flash Player. It is only surpassed by
the request to keep developing Flash Builder for Linux, which
I think is an important issue, but this issue is much more important. If you haven't already, create an account on Adobe's issue tracker and vote for this issue.