Invalid certificate from Android

[mrmarkuz (Markus Neuberger)]

You may use the old chain:

Upcoming change to default Let's Encrypt chain

On 30 September 2021 the DST Root CA X3 has expired. This certificate is part of Let’s Encrypt full chain and it’s used to support old devices with Android <= 7. According to this chart, around 7% of existing Android devices. To make things work, Let’s Encrypt leverages on a never-fixed bug of old Android versions. This choice has been proven to raise more issues even on recent devices and software which, of course, have their own bugs (see here and here). As Nethesis, we had to face the pro…