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And you would need to:
upgrade your SonarQube version to - at least - 7.7 (the best would be 7.9 LTS version, which is the last LTS and supported version), as Bitbucket Pull Request decoration has been added after 7.7 version of SonarQube
have a commercial license (Developer, Enterprise or Data Center) as branch analysis and PR decoration are available only on commercial editions → Fill in the form so we can send you a trial key : Try Now Developer Edition