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Many processes are different for different issue types. Unless you are a committer, submit only Bugs.
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Features get tracked against as larger work items while Bugs and Tweaks do not. Tests and Tasks may be allowed at times when Features, Tweaks or Bugs are restricted. Bugs are counted in quality metrics while other types are not. As a result it's important to get the issue type right. Calling something a Bug rather than a Feature or calling any kind of code change a Task are the most common mistakes.
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