anamethatisnt

I imagine something like Ontrack will quote you at least $1000
If you consider the data worth that then I would go for one of the big known firms.
If not then I would start researching how to replace a pcb and risk losing the data.

Yeah, I've written some custom css to get some better wrapping of libraries and such.
There's also the community themes worth looking into.
https://jellyfin.org/docs/general/clients/css-customization/#community-themes

The space inefficiency is definitely there.
I find that clients, such as Jellyfin, Moonlight and Signal, works just fine as flatpaks but with those three apps my /var/lib/flatpak/ lands on 6.4GB.
When I temporarily had Discord installed it grew to 6.7GB, so the inefficiency is frontloaded and lessens the more of them you use.

Just played a bunch of episodes on Fedora KDE (Flatpak from flathub, Jellyfin client v.1.11.1, Jellyfin server v.10.10.6) without any trouble.

I would go for a reverse proxy to get ssl running.
https://jellyfin.org/docs/general/networking/#running-jellyfin-behind-a-reverse-proxy

Handling users with forgotten passwords is, sadly, a manual chore for the administrator.
https://jellyfin.org/docs/general/server/users/adding-managing-users#profile

Ah, if you're allergic to flatpaks and can't convince your distribution to include it in their repository then you can always build it yourself - https://github.com/jellyfin/jellyfin-media-player
Or just use their web based client with a browser of your choice. :)

As I was curious, Findroid gives you an android client that allows offline mode and downloading/playing/removing movies from the client.
Seems Infuse Pro (paid) version also has support for it if you're an iPhone user.
edit: I see the discussion regarding filesizes and I believe that Findroid is downloading the raw file in the background, so for those that wish for smaller transcoded versions in the cache it isn't a solution. I don't own any apple devices so can't tell how Infuse handles it.

The default Jellyfin client isn't great for audiobooks.
For Apple iOS you might wanna look at https://github.com/LeoKlaus/plappa
For Android I would look at https://github.com/advplyr/audiobookshelf
Personally I just download the audiobooks from Jellyfin and play it in https://f-droid.org/packages/com.prangesoftwaresolutions.audioanchor/

They too put a whole lot behind their subscription though
https://emby.media/support/articles/Premiere-Feature-Matrix.html

I mean, except for Tizen OS isn't most available? You can find the client for Android, Android TV, Windows, Linux (Flatpak), macos, apple ios, and more.
https://jellyfin.org/downloads/clients/

I didn't enjoy using Jellyfin for audiobooks, on my android I use the Jellyfin client to download the book I wanna listen to and then I use AudioAnchor for listening to it.

I haven't used Plex myself but Jellyfin doesn't create any kind of meta files in the library folders. If that is true for Plex as well then I don't see why it would be a problem to point them at the same shared library.