Non-Project Files Protection dialog
If you want to work with these files, add them to the content root. Learn more from Configuring project structure.
If you want to edit these files only once without adding them to your project, use one of the options in the dialog:
I want to edit this file anyway: select this option to disable protection for the listed files.
I want to edit all files in this directory: select this option to disable protection for the listed files and all files in the same directory.
I want to edit any non-project file in the current session: select this option to disable protection.
All options are effective during the current session, once the IDE is restarted, protection will be re-enabled. Also, you cannot change your decision for a particular file within the current session.