sooooo it seems to come down to:
1. stay with firefox 45 and use firebug 2. update to firefox 52 abandon firebug, and stick to developer tools. *unfortunately … it seems more of a firefox then of a firebug issue. firebug 2.0.18 „inspect element“ works fine under Firefox 45.4.0, but fails under Firefox 52.0a2.* http://getfirebug.com/releases/firebug/2.0/firebug-2.0.18.xpi <http://dwaves.de/wp-content/uploads/2017/01/firebug-2.0.18.xpi_.gz> so doing the: about:config search and double click this entry to change it to: xpinstall.signatures.required = false *DOES NOT HELP in Firefox 52 (even in developer edition) * -- You received this message because you are subscribed to the Google Groups "Firebug" group. To unsubscribe from this group and stop receiving emails from it, send an email to firebug+unsubscr...@googlegroups.com. To post to this group, send email to firebug@googlegroups.com. Visit this group at https://groups.google.com/group/firebug. To view this discussion on the web visit https://groups.google.com/d/msgid/firebug/b977cd60-6579-4d66-b99c-0eb96f547dc3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
