Sider allows closing each issue within a pull request to assert the issue is “wontfix” or “confirmed”. This feature is available to all users in the GitHub repository who have write permission or higher. See Permissions for details.
Now, users with admin permissions for the repository can restrict closing issues only to users with admin permissions. To enable this setting, click the “Admin” tab from the Repository Settings and click the “Restrict close button”.
After enabling this for all users who have write permissions, the Close button will be disabled like the following:
Please also see the documentation for details.