system/HTTP/Negotiate.php
public function media(array $supported, bool $strictMatch = false): string
	{
		return $this->getBestMatch($supported, $this->request->getHeaderLine('accept'), true, $strictMatch);
	}
public function media(array $supported, bool $strictMatch = false): string
	{
		return $this->getBestMatch($supported, $this->request->getHeaderLine('accept'), true, $strictMatch);
	}
Determines the best content-type to use based on the $supported
types the application says it supports, and the types requested
by the client.

If no match is found, the first, highest-ranking client requested
type is returned.

@param array   $supported
@param boolean $strictMatch If TRUE, will return an empty string when no match found.
If FALSE, will return the first supported element.

@return string