[Log Form] Fix issue in FF

If FF loads the page from browser cache then it is already fully loaded when the observing starts and thus the observer callback isn't called.
To circumvent this, we add a dummy element (and immediately remove it) to force a call to the observer callback.
Note that in Chrome or if one forces a page reload from the server this isn't an issue.

gc_little_helper_II.user.js

@@ -5473,6 +5473,10 @@ var mainGC = function() {
             observer.observe(document.body, config);
         });
         logviewObserver.observe(document.body, config);
+        // Safeguard: if FF loads the page from browser cache then it is already fully loaded at this point,
+        // therefore add a dummy element (and immediately remove it) to force a call to the observer callback.
+        // In Chrome or if one forces a page reload from the server this isn't an issue.
+        $('body').append('<div id="gclh_dummy"></div>'); $('div#gclh_dummy').remove();
     }
 
 // Improve Mail.