Perhaps there is a solution in an update to the Skype add on you see in your Firefox profile as well?

Looks like it can be reinstalled from https://support.skype.com/en/faq/FA10.../how-do-i-get-skype-click-to-call and that the community might have some insight. In general, unresponsive scripts can be troubleshooted in Firefox with these steps: Warning Unresponsive script - What it means and how to fix it

The full URL did not appear in your post (has ... in the middle). Does it point to the Skype extension as the script that isn't working?

Another common cause of unresponsive script errors on Windows 7 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. There is a hidden setting to disable it; I suggest trying this for a day to see whether it helps:

(A) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(B) In the search box above the list, type or paste flash and pause while the list is filtered

(C) Double-click the dom.ipc.plugins.flash.disable-protected-mode preference to switch its value from false to true.

This might not take effect until all Flash has been unloaded for a few minutes, or you close Firefox.

• https://www.google.com/search?q=jquery-2.1.0.min.js+skype

• http://community.skype.com/t5/Windows-desktop-client/After-installing-Skype-Outlook-and-explore-get-script-error/td-p/3691685

Uninstall the optional Skype Click to Call add-on in "Add/Remove Programs" or "Programs and Features" in "Control Panel".

Thank you jscher2000 for your suggestion. I just did what you said, closed Firefox and reopened it and--so far, so good! What a relief. Hope it continues this well. Thanks.