The best replacement for bugzilla is mantis.

The best alternatives to bugzilla are rated as following:
★★★★★  mantis
★★★★★  jira
★★★★★  trac
★★  redmine
★★  clearquest
★★  fogbugz
★  bloodhound
★  quality center
★  hp quality center
★  youtrack
★  osticket
★  rt
  gnats
  test director

Your alternative for bugzilla is not listed? Suggest!
Speaking about bugzilla, one probably shouldn't forget about svn.

Other search terms related to bugzilla and their ratings are:
★★★★★ svn
★★★★ svn integration
★ testopia
★ testlink
You have in mind a companion for bugzilla and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of bugzilla in all years. Click on graph for more.
bugzilla
mantis
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