We're not aware of any hangs on launch related to 10.12.6 (or in general.) Please sample the application using Activity Monitor and attach that here for us to review. You might try setting aside your preferences as well to see if it's something specific in there. Apologies for the hiccup.
Senior Mac Developer, Sourcetree
Supported Platforms macOS Windows We recently introduced support for additional hosting services such as GitHub Enterprise, GitLab (Cloud, Community Edition, Enterprise Edition), and...
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