Site URL Incorrect - Localhost or internal dev server

I need to work on creating a template and will be extending the plugin to pull data from the database from another table/source. However, SIte URL incorrect keeps popping. How can I do development/testing without being on a live site URL for the plugin? Thank you!

Hi,

Your wordpress website must have correct unique domain name in settings. It will be okay to use something like: http://mywebsite1.local or http://mywebsite1.dev etc, but not http://localhost as it's too common and restricted for usage to avoid multiple websites under same domain name. Keep in mind please that server where located dev website must also have access to internet.

We remain at your service.

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