It sounds like you are getting a random named website claiming to have a urgent Firefox update. This is not from Mozilla or the Firefox web browser. The fake firefox-patch.exe and firefox-patch.js files can install things like trojans, viruses, or unwanted software on Windows based on past reports if the user runs them.

The updates are done internally in Firefox (with a .mar type of file) whether on Windows, Mac OSX or Linux or by download from mozilla.org like say www.mozilla.org/firefox/all/

You could try using a adblocker extension like uBlock Origin to block theses fake ads if you keep getting them. https://addons.mozilla.org/firefox/addon/ublock-origin/

Unfortunately this has gone on for over a month now with one or two new sites reported almost everyday. https://support.mozilla.org/en-US/forums/contributors/712056/ and https://support.mozilla.org/en-US/forums/contributors/712075

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Warning Unresponsive script - What it means and how to fix it

Another common cause of unresponsive script errors on Windows Vista-10 is the protected mode feature of the Flash player plugin. That feature has security benefits, but seems to have serious compatibility issues on some systems. You can disable it using the Add-ons page. 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.