Web Extension Error: `TypeError: Failed to fetch`

[Frederisk]

Full error message:

Access to fetch at 'https://github.com/' from origin 'https://v--05jqmiibrpsovhruor6qb71uo3ga8g9dbv6hr2q5l7elh6s78j7p.vscode-cdn.net' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
ErrorName: TypeError; ErrorMessage: Failed to fetch.

Extension Guides - Web Extensions:

For accessing web resources, the Fetch API must be used. Accessed resources need to support Cross-Origin Resource Sharing (CORS)

The problem is caused by the browser's security policy and depends on the backend settings, and this is part of the security specification. As a part of normal web application, this extension cannot bypass this restriction in a non-destructive way.

For more details see: https://fetch.spec.whatwg.org/

Note: The error occurs when the response is received, not when it is sent. Generally, operation messages can be sent successfully.