Description
Closes #9204, #9211
Before that, the method could not get a value if the POST, GET... data is stored as a list.
This affected FeatureTestTrait

I think there is a potential error in fetchGlobal() - it does not understand the numeric keys $_GET[0]['one'] = 1

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide