Looking for learning material data change

[CET]

Hi,

I am a beginner Jellyfin user, I installed it on a Minisforum Air in Docker successfully. I dismantled a custom theme and used parts of it through the branding CSS box to achieve custom look. I'd like to learn more about the architecture, services and overall structure of Jellyfin.
So I figured I need an initial goal. So, since I hate the current actor page (when you click on a Cast&Crew member and see the media they contributed to).

My problem is with the Shows and Episodes sections. I don't like that we have two. I would like to see one section (Shows) and list all the shows the person contributed to in this list (so hide the Episodes section and add all the Shows to the list above, basically).

Now, obviously I figured out how to hide the Episodes section from CSS, that's not a complicated thing to do, but changing or capturing data is another thing.

So I'm looking for either tutorial, docs or even videos explaining where to start with this (capturing the Episodes data and adding to the Shows section as tv-shows).
Or even someone to explain if there are no teaching material in the subject.

Obviously I tried to check Jellyfin's own webpages but it's a little bit confusing to me still if I need to write a plugin, a theme or is it achievable by only styling somehow? Custom JS or proper dataflow plugin?

Any help will be appreciated!

ps: I'm a software engineer and worked more than a decade in web development too, so I don't need absolute beginner's talk, just to turn me into the right direction. I also have an absolutely no-AI policy, I won't ask any of those and I appreciate if you don't feed me AI answers either. I'll attempt to learn, not exploiting other people's work if possible.

[TheDreadPirate]

Each page performs its own queries. While you can hide data that is queried from being displayed with CSS, as you've already done, you cannot add new data the page with CSS if the data is never queried to begin with.

You would need to modify jellyfin-web to do what you're asking. Something I wouldn't recommend doing as it would break each time you update. Or you would need to maintain and rebase your own fork regularly.

AFAIK, there are no tutorials, docs, or videos for teaching how the innards of Jellyfin work. You just have to dive in and figure it out.