Check out example codes for "ionic iosa app not making requests to server". It will help you in understanding the concepts better.

Code Example 1

<meta http-equiv="Content-Security-Policy" content="default-src 'none'; script-src 'self' 'unsafe-inline' 'unsafe-eval'; connect-src *; img-src 'self' data:; style-src 'self'; font-src 'self';">

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