Description of problem: If you use JS and goto a URL like: https://bugzilla.redhat.com/enter_bug.cgi?product=Fedora&component=yum&version=rawhide ...the new magic component box is still blank, instead of being prefilled with yum.
You should see the following hint text under the Component box: "(Start typing a name, and a drop down box will be shown. You can hover over the component name for a description.)" I just tested this again using Firefox 23 and the behaviour was as expected. When I type "yum" in the Component box, a drop-down list appears and is dynamically populated with al lthe components containing "yum" as a substring -- "yum" itself is the second last one in the list. When I hover the mouse over "yum" the borwser show the hint "RPM installer/updater". Are you seeing something different?
Please ignore my previous comment. For some reason I misread the report as being about entering a componet rahter than specifying one in the URL. This bug actually appears to be a duplicate of Bug 1016162, which was fixed in RH Bugzilla 4.4.1010, released on November 3, 2013. *** This bug has been marked as a duplicate of bug 1016162 ***