Bundled git not compatible with macOS 10.14

My SourceTree 4.1.8 automatically updated to 4.1.9 with no warning. 4.1.9 bundles a git binary that is not compatible with my system, macOS 10.14.6. This causes SourceTree to lock up constantly or crash, making it very difficult to choose to use a separate git installation instead of the built-in one. Even after I managed to choose a system git, SourceTree keeps crashing, and is unusable.