I have a weird issue and after a few weeks of investigation I think I may have found the cause : Cloudfront & Googlebot.
Context : I launched a French website that compares and combines all ground transport in France & Europe.
Thanks to all these combinations we are able to produce a lot of unique content (based both on historical & potential data).
Problem : Google intermittently fails to fetch data from Cloudfront... It means than one out of five it will fail to load js & css ressources. (The client side is in angularjs).
In that case nothing render on the page and google think it's a blank page.
When I go on the Google Search Console (GSC)and send pages manually they're all doing good and start ranking. However one out of 4 or five Google won't load ressources and displays errors and unrank the page.
sometimes it has errors on getting images and sometimes it's even worst it is the whole minified app.js file. In this case nothing at all is displayed.
I cannot reproduce the errors outside the Google Search Console. Is that possible that google is timing out too soon to get all the files ?