The protected mode feature of the Flash player plugin fragments Flash content into separate processes and uses an external EXE to run them with lower privileges. I'm sure this does slow down Flash, so you could compare with this feature disabled.

Either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. On the right side, find "Shockwave Flash" and click the More link. Then uncheck the box for "Enable Adobe Flash protected mode" and try that for a day to see whether it helps.

Note: This doesn't take effect until at least 3 minutes after Firefox has unloaded all Flash content. The easiest way to ensure that is to exit Firefox and start it up again.

L33T_BEANS said

I'm using the latest commercial versions of both Firefox and Adobe Flash. I'm currently using Google Chrome which doesn't have this issue with the Flash plugin so I'm inclined to rule out Adobe but I could easily be wrong.

The Google Chrome browser comes with a Pepper-based Flash Player PPAPI and does not use the NPAPI Flash Player that browsers like Firefox and SeaMonkey uses.

This is not a cure, but should let the web page load without crashing.

Flash block {web link} Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way, but if you want to see it, just click on it

Thanks for the help, I can use my favourite browser again!