: Sites hosting these files often use aggressive "adware" or "malware" injectors that can infect your device via "Download" buttons that are actually scripts.
: The term "extra quality" or possibly misinterpreted as part of the string could imply that the uploader or seeker is looking for or providing a higher quality version of the content than standard.
: Likely metadata regarding the video resolution or the specific uploader's "observer" tag. Google Transparency Report Important Considerations