1- apply D16779 to Kate, rebuild and reinstall the kate-ctags plugin
2- apply D16927 to KTextEditor, rebuild, reinstall
3- load that plugin in KDevelop; observe contextmenu action duplication (once for each document that has opened a contextmenu)
4- apply this patch, rebuild and reinstall libKDevPlatformShell
5- repeat 2, contextmenu is free of duplicates