Notes from the Google Webmaster Hangout on the 24th of January, 2017.
Mobile Interstitial Penalty is Calculated on Recrawl
The mobile interstitial penalty is calculated in near real time as pages are crawled.
App Banner Sized Mobile Interstitials are OK
There is no explicit percentage size of mobile interstitials which are OK, but John suggests a normal app banner size should be OK.
Mobile Interstitial Detection Will Improve
Google will be improving the interstitial classifiers over time as they find more examples, so any interstitials which are not affected yet might become an issue in the future.
Noindex Can Mitigate Quality Issues
You can noindex pages to prevent low-quality pages affecting the Panda algorithm.
AMP Pages Don’t Affect Quality Unless they are Canonical
If you use AMP pages as your canonical pages, they will affect your quality metrics, but if they are canonicalised to another page they won’t.
Google Isn’t Planning to Increase Rankings on HTTPS
Google isn’t planning to increase the rankings for HTTPS pages unless it becomes a quality issue.
Pre-rendered Pages Are Easier To Test
No Limits to Link Titles, Image Titles and Alt Tags Lengths
There are no word limits to link titles, image title and alt text.
Google Mobile-first Index will include Link Title Text
Google isn’t planning to change the way they index link title text when they move to mobile-first indexing.