In Chrome I noticed that when searching in Google only the first search results are marked as safe or unsafe.
The results that appear at the bottom after the search page loads when you scroll down are not marked as safe or unsafe, the logo does not appear.
I simply search for the word “pippo” in Google.
The first results are marked by Avast (see image 1) the subsequent results at the bottom of the page which are loaded as you move down with the mouse are no longer marked by the extension (see image 2). So it seems like it’s a partial link check and not a total check on the entire search.
This behavior would be directly related to Avasts’ business relationships with whatever browser company is involved, what legal agreements were made between them, what country, what overall restrictions legally placed on them, what region and language, and so on.
The program in question, Avast Online Security, has to be designed to take all these factors into account, and more, and still provide a modicum of ratings protection for free.
Even if a site is marked as green arrow, this does not mean it is always clean, just so you know. There may be a higher probability it is, but that is all we (you and I) would know. The converse is true of a site marked in red, it may have had malware removed, and has been properly updated and remedied, so it is now clean but still shows as red.
Point is, this is a guide and is meant to help us make better decisions on what site to visit.