This behavior is often found among unscrupulous developers who retroactively monetize their free products. The only way to protect yourself from this is to choose trusted suppliers with transparent rules. Before implementing the code, study the reviews of colleagues and see how the element looks on other resources.

I ran into the same problem a couple of months ago when a free script ruined the look of the site with ads. I started looking for a clean alternative among well-known meteorological platforms. On the advice of a colleague, I installed the https://billing.meteoprog.com/ marker, having previously checked the structure of the output code. There are no left-hand scripts or ad blocks there. I monitor his work regularly, everything is fair and without unpleasant surprises.