What are these errors?

Question

Browsers

Site on Opencart 1.5.4.1, error log screen from the product page.
What are these errors, at least in general, tell me (in layout or in copyright, or maybe something malicious in general),
just at least understand where to start correcting. Where the error is due to the http link, this is understandable, you need to fix the link address, but what about the rest?

Answer 1

This is an ad blocker or other third-party extension that blocks certain resources (because of this, “ERR_BLOCKED_ BY_CLIENT ” is written).
SyntaxError: Check the validity of your JSON you are receiving/sending.

Answer 2

Adblock works