Not sure about the self-host part but Jabref and Zotero might fit.
This is a good starting point if you want to dive in.
I will realy apperiate it if you could send me one too. Thanks.
What are the reasons for the Pi Hole to Adguatd switch?
YT plugin for Kodi is quite decent. Have it daily in use, no issues so far.
It's trillan you are talking about. I am old too :D
Using Argon NEO and quite like it. In my case it was important to have the ability to use a HAT (HiFiBerry).
You probably mean Radicale. Baikal is an option too.
Not sure about the self-host part but Jabref and Zotero might fit.