Google may not index or rank the content within the click to expand menus or tabs on the website. The news comes from Barry Schwartz of Search Engine Roundtable, after he got a response from John Mueller on Google+. Barry was covering a thread entered on click to expand content not being either indexed or ranked by Google. He decided to ask John Mueller of Google this query in live hangout on Google+ around one week back and received a surpassing response.
John said content within click to expand menus or tabs could be discounted as Google knows it is being hidden from users. As a result of this, the page may not be ranked for content by Google within those sections as it knows users do not view content by default.
Barry has commented that this makes it seem Google is saying content within these tabs will be given no importance. Amazon had a lot of tabs but now the output of the content occurs directly on the page. This makes users go on a scrolling spree to see content, Barry adds.
Google's own help documents do use click to expand but only for viewing the questions. Clicking on a query itself does not ensure that the user reaches a new page with listed answers as against answers beneath the question as can be observed in the click to expand content:Content Within Tabs and Click To Expand Might Not Be Either Ranked or Indexed: Google!,