system/HTTP/ContentSecurityPolicy.php
public function addPluginType($mime, ?bool $explicitReporting = null)
	{
		$this->addOption($mime, 'pluginTypes', $explicitReporting ?? $this->reportOnly);

		return $this;
	}
public function addPluginType($mime, ?bool $explicitReporting = null)
	{
		$this->addOption($mime, 'pluginTypes', $explicitReporting ?? $this->reportOnly);

		return $this;
	}
Limits the types of plugins that can be used. Can be either
a URI class or a simple string.

@see http://www.w3.org/TR/CSP/#directive-plugin-types

@param string|array $mime              One or more plugin mime types, separate by spaces
@param boolean|null $explicitReporting

@return $this