This is certainly due to missing username and email in the global configuration of git. Easy way to solve this is through IDE:

• From top Menubar: Git > Settings

• Type the username and email that will be publicly visible in your commits

• After this, save pending changes to your project and restart Visual Studio.

• The Commit button should now be usable within the IDE after reopening the project.

These actions performed are equivalent to CLI approach of:

git config --global user.name "Your Username"

git config --global user.email "[email protected]"

P.S.: It'd be good to set the "Default Branch Name" to main as it defaults to master.