Both are usable but not optimised and not currently a particularly good experience. My experience is based on Mobian on Pinephone but it should be pretty much the same on the L5.
Bitwarden desktop electron can be installed from flathub and runs. It’s pretty slow and clunky though and electron apps in general display slightly blurred (if they run at all). So it’s possible to open it and copy a password from it but if you’re expecting the Android/iOS autofill experience you’ll be disappointed.
Jellyfin works via MPV shim (https://github.com/iwalton3/jellyfin-mpv-shim) or web browser. In both cases performance isn’t really good enough to make this suitable for daily use either, both in terms of scrolling around the interface and in terms of video playback but this may be better on the L5 than the PP given it’s better GPU.