I had exactly the same problem, Sourcetree 1.6 took until 3gb of memory loading file's list. I could solve this issue installing the 1.5 version. Here, you can download it:
Supported Platforms macOS Windows To make using Sourcetree as simple yet powerful as possible we embed (bundle) dependencies such as Git, Git LFS, and Mercurial. We strive to keep these...
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