My company uses Roundcube for Webmail and offers Thunderbird as a native client. It’s always great to see free software in a corporate environment.
Roundcube should work pretty well for you: https://roundcube.net/
I always need
CLI:
Still a ridiculous move. If I buy an appliance, I pay for it and I own it. I am allowed to do with it whatever I want. If I want to use my own solution for controlling it, hosted on my own server, I should have every right to do so. Fuck corporations and their shitty cloud solutions.
SAP, closely followed by IBM/Lotus/(I have no idea which random company they were sold to) Notes
I fucking hate this corporate bullshit software