Over the past few years, Let's Encrypt has been issuing certificates for TLS encryption for most domains, allowing sites to use secure encryption over HTTPS. However, in two months the situation will change, as the company has announced a revision of its policy.
On most platforms, thanks to an agreement between IdenTrust and Let's Encrypt, the so-called cross-signature has been used for many years, but on September 1 of next year, this agreement expires, the parties do not intend to renew it, Let's Encrypt goes to work only under its root certificate.
Thus, operating systems and browsers that have lost Let's Encrypt's support will no longer be able to display sites that used certificates of this company. Since the problem may be observed on all devices older than Android 7.1.1, we can say that about a third of Android devices will experience certain difficulties. One solution in this situation may be the use of Firefox, which has a built-in certificate base.