Sourcetree is using the standard macOS sidebar so these behaviors are a part of the platform, like in Finder or Mail.
If a section has content a Show/Hide button appears when you move your cursor over that group's header. If a section doesn't have any content, the header is shown but there is no Show/Hide button because there's no content for it do so with and no need for a visual indicator.
Principal 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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