There is an underlying shortcoming in the technology that w use for the S3Drive which results in user managed CAs on the system level not being included in the system HTTP library.
There is a relevant issue that will hopefully be able to resolve it: https://github.com/dart-lang/sdk/issues/48056
There are some workarounds that we could implement by allowing user to upload their certificates to the app e.g. https://api.flutter.dev/flutter/dart-io/SecurityContext/setTrustedCertificates.html
or by allow certificate whitelisting (even if they fail chain validation)... however this feature isn't the highest priority given our other work.
Let's use this item to keep track of the updates.(edited)