There will be a Google Update in May this year where CLS (cumulative layout shifting) becomes an important ranking factor. On our site we embed some iframes (mostly live tickers etc.). At some point we used fixed height and width values for these iframes but that was not an optimal solution because the content for these iframes changed on a regular base. When it was an iframe that displayed game day data of sport events there was either a lot of white space when there was just one match on that day or it was cut off when there were 9 matches that day. So we implemented a iframe resizing solution with pym script. That made the site look a lot better and increased usability. Some iframes are even more interactive and have tab navigations etc. and the current iframe resizing also works with that - the height is also adjusted then. And since this is caused by user interaction there shouldn't be Google punishment for this. Embedding and implementation work like this: http://blog.apps.npr.org/pym.js/
I did some research but unfortunately could not find a solution to keep the usability but get rid of the CLS. Does anyone have some tips, useful links or an idea how to solve this?
