Sometimes Leankoala can't find elements by a CSS selector that can definitively by found in the browsers DOM. There are some reasons why that can happen: 

  • Advertisement: Some ads change the DOM in a way it breaks. The browser will repair these anomalies in many cases. Leankoala does not or at least not as intensive as a Chrome and others do. Really broken HTML can make Leankoala stumble. But in most cases, we will fix broken HTML.
When such a problem occurs it's a good idea to have a look at the HTML code Leankoala checks. It can be found on the attributes tab on the "Incidents Insights" when clicking on info at an incident. If the CSS selector cannot be found in the text Leankoala is right and the selector is not there. If it is found chances are good that JavaScript broke the code. If it is possible to fix that code because it's in the userland, fix it.
If it is caused by a third-party solution the fix is not that easy. If the CSS selector was already part of the HTML that was generated by the web server the simplest solution is to switch from DOM to HTML. 
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