I think you might have "click to play" turned on. I haven't tested it myself, but in looking at the screen shots in this CNET article, it does appear that like other site-specific permissions, you should be able to manually change the permission if the dialog isn't working well:

To call up the Page Info dialog on any page, you can use:

• right-click > View Page Info > Permissions tab
• Tools menu > Page Info > Permissions tab

Does that match what you're seeing?

Or, to turn this all off completely and go back to automatically running plugins, you can return to about:config and reset plugins.click_to_play to its default value of false.

Does that help?

By the way, I notice from your system info that you have a user.js file. If you notice settings being changed each time you restart Firefox, it could be due to an instruction in that file. To inspect and/or deactivate that file, you can do this:

Open your current Firefox settings (AKA Firefox profile) folder using

Help > Troubleshooting Information > "Show Folder" button

Switch back to Firefox and Exit

Pause while Firefox finishes its cleanup, then rename user.js to user_js.txt so you could, if you like, view it in a text editor (and Firefox will not execute it).

Restart Firefox. Hopefully now your changes will not be overridden.

Note that Mozilla recently has decided to blocklist a lot of Flash 11.0 - 11.2 versions.

• bug 850734 - For 3/18: Please CTP block 11.0.*-11.2.202.275 (not including 275)

• https://support.mozilla.org/kb/why-do-i-have-click-activate-plugins

Thanks jscher2000, as per the attached, you can see there's nothing to change on the permissions tab for that page, and as for the click to play, it is already set as false.

It would appear that the only way to get round the problem was to install the latest version of flash player as I was using the old version to get around the opening in new windows problems that has been going on for months with Firefox

Thanks about the user.js file, I had forgot all about that when a rogue page tried to install a babylon toobar, now deleted. :-).

I forgot about the "old plugin" variation of click-to-play.

Updating is good. What is the new window problem -- the one where Firefox switches the active window back to the last one you were using? I've noticed that. It is annoying, but not so annoying that I've stopped to research the status of a fix.

When I check your "More system details" list it appears that the updater failed to clean up an older version of the plugin. This thread is about a different plugin, but the strategy for finding and removing the older one is the same: Multiple versions of Shockwave Director.

You have two versions of Flash, 9.0 and 11.1. Please uninstall them both and update to Flash 11.6