GCE v2.2.1 nav is disabled after running Firebug

There is an interaction between the shortcode in a widget and Firebug (in Firefox) or Developer’s Console (in Chrome).

Test Sequence:
1) activate plugin and verify navigation & tooltips are working
2) activate Firebug
3) navigation and tooltips are no longer working
4) turn off Firebug
5) verify nav and tooltips are still not working.
6) close browser and restart – verify nav & tooltips are back to working.

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