1, On Mac platform, I can hide/unhide the toolbar of sourcetree, and many softwares on the Windows platform allow users to hide/unhide the toolbar. I think it is a good design because most of time we want to focus on the main pane. And the toolbar of SourceTree for Windows is too big for me.

2, It's a nice feature to allow users customize the toolbar. Some friends want to rearrange the shortcuts, or hide texts under the icons to save space and make the UI more concise/elegant.