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Implemented because now it can operate on the selected files.

Removing these options currently is only possible by editing the global .gitconfig file in the %USERPROFILE% directory using a text editor.

Do you know that you can open the log for repositories without opening them?

This is intentionally, so you don't open all repositories and complain about having a memory hog and bad performance. Why do you keep your frequently used repositories open?

Implemented in SmartGit 17. Can be configured with the VM option smartgit.branch.replaceInvalidCharsWith defaulting to "_".

Until implemented you may create your own external tool that performs the required "git clean" command.