Getting a Firefox warning on your Silverlight 1.0 apps? Here’s the fix.

Jaime Rodriguez has a nice explanation of the problem, and workarounds for the issue.

The explanation:
The warning is prompted by Mozilla’s heuristics to check on long running scripts (details on these heuristics way below). The problem is that for silverlight or any plug-in that makes Javascript calls, Firefox some times does not reset the timer for the scripts called from plug-ins: If you fire multiple events from a plug-in the events are obviously handled sequentially, if a new event happens while an event handler is executing, then Firefox does not reset its counter for the script time out; it measures the time from these two events as a single script.