Google starting to enforce mobile-friendly web design as a search ranking factor
This week the traffic to one of my sites is exhibiting a steep traffic fall-off. For years it has had a solid 1000 visitors per day, or so, and at the beginning of March the traffic started to slowly diminish, then on Wednesday April 3 the traffic fell off steeply. Usually this site has a fall-off on the weekends, so this particular change is ominous. In the Google Webmasters tools is a clue - that at the beginning of March there is suddenly many reports of mobile usability issues. The two are likely connected as Google has long warned of a plan to downgrade sites that are not mobile friendly.
How does a collapsed section affect on page SEO?
We might want to optimize the visual space on a web page to display a large amount of text without it looking like "too many words". Visitors seeing a long block of text might be put off and go somewhere less verbose. Using an accordion to collapse sections of text -- I have an example below -- can minimize the vertical space required to display the page. But it requires putting text inside a div tag with "display - none" and the search engines might think the page has negative SEO factors. But by some simple observation we can see that's not the case.