Secure websites will stop loading on phones running Android 7.1 or older from September 2021
Daily Mail
US-based certificate authority Let's Encrypt said a change in its criteria from next September will mean old Android operating systems won't trust its root certificates.
https://www.dailymail.co.uk/sciencetech/article-8929127/Secure-websites-stop-loading-phones-running-Android-7-1-older-September-2021.html?ns_mchannel=rss&ns_campaign=1490&ito=1490