The first or the second?

The first I don’t think is going to be upgraded. The software has development maintained but for that is better just to use other apps based on it.

The second, I tell you that is normal. Some websites referencing studies and mostly old ones have a very lack of maintenance.

The best a person could do is just get the DOI links and try to download the papers using a sci-hub instance.

BTW, I didn’t see any request to download any certificate or accept them. Check your ca-certificates package to know if it is upgraded.

If you are using Android, I think it is upgraded with the own system.

In addition, both websites work correctly.