Query string contains a question mark
This means that the URL in question contains more than one question mark in the URL path.
Why is this important?
In a URL, the query starts with a question mark - the question mark is used as a separator, and is not part of the query string.
If you also include a question mark in the query string, this would be treated as a literal question mark (i.e. it has no significance beyond that of a regular character). Whilst this is not invalid, it is quite unusual, and may indicate some sort of issue with how URLs are generated, so it could warrant further investigation.
What does the Hint check?
This Hint will trigger for any internal URL which contains a question mark in the query string, and therefore multiple question marks in the URL.
Examples that trigger this Hint
The Hint would trigger for any URL with two or more question marks, e.g. https://sitebulb.com/list.html?page=1&id=999&?page=2
Why is this Hint marked 'Advisory'?
In Sitebulb, this Hint is Advisory, as it does not represent a clear issue. A question mark in the query string does not invalidate the code, and both browsers and search engines can handle them.
However, since most URLs are dynamically generated by a script or CMS that powers the website, the existence of such URLs may imply that URLs are not being created correctly.
As such, it might be worth running this by the website's developer to check that there is no bigger issue at play.