Remove titlebars from slack, vscode,postman, etc

 VSCode: https://stackoverflow.com/questions/47255696/way-to-disable-the-visual-studio-code-editor-title-bar#:~:text=You%20can%20use%20this%20setting,and%20set%20it%20to%20custom.

Postman: https://github.com/postmanlabs/postman-app-support/issues/11197#issuecomment-2118886224