When you go to a duplicate bug and want to switch the master bug using the ajax UI, a second <edit> button appears below the "Duplicate of ..." line. The fist screenshot shows how it looks like before you edit it, the second one shows the 2 edit buttons.
When you go to a duplicate bug and want to switch the master bug using the ajax UI, a second <edit> button appears below the "Duplicate of ..." line. The fist screenshot shows how it looks like before you edit it, the second one shows the 2 edit buttons.