Wanted to get rid of the annoying not secure https session so found these instructions.

https://community.ui.com/questions/How-to-install-a-Valid-Certificate-on-the-ER-version-1-8-5-and-above/71d1fb1b-198d-4114-910c-1a24326104b4#comment/6b468339-fe58-4d9c-b6f7-d0cbbf64d541

Used zerossl.com for the 90d certificate. So every 90d I have to install the updated cert.

Quick instructions:

1. CSR -> zerossl
2. Generates cert and ca-bundle (as .crt files)
3. Download and save on local computer, extract zip
4. Copy cert into server.crt on ER4 and append key file (cat <keyfile> >> server.crt)
5. Copy ca-bundle into ca-bundle.crt on ER4

That should work for updates.