Firebug stops highlighting elements after a while

[Randolf Rinconadolf]

This has been happening to me for a while now (a few months probably). When I click on something on the HTML tab, it's supposed to highlight that element in the browser page. It does this for a while (an hour maybe?) but then it stops highlighting.  If I minimize Firebug and open it again, still it doesn't highlight. If I deactivate it and activate it again, still nothing. If I close Firefox and open it again, then it starts working as expected.

[Sebastian Zartner]

Could be a conflict with another extension.
Does the Firefox Error Console (accessible via Ctrl+Shift+J) display anything related?
Did you already try that on a fresh profile?

Sebastian