Fix for JSON meta data download

[snipem]

Added fixes according to #13651 and user @remitamine

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The code was initially posted by user @remitamine. @remitamine Please give you approval in this Pull Request.

What is the purpose of your pull request?

• Bug fix
• Improvement
• New extractor
• New feature

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Description of your pull request and other information

Fixes the generic extraction problem of JSON data from NBC sites by adding a prefix to the URL to be downloaded. The code was first introduced by user @remitamine in the #13651 discussion.