unable to set parameters for opensubtitles plugin

Hi !

Describe the bug

I don't remember being able to set up the opensubtitles plugin since I installed jellyfin on yunohost. when I ask for the parameters of that particular plugin in Dashboard>Plugins they are not displayed right, the form is either behind the plugins buttons or in front of them.

jellyfin-plugin-settings-1 jellyfin-plugin-settings-2

in either cases the back and home buttons on the page don't work. If I reload the page, the form is displayed but filling it and clicking on the save button only reload the page and show an empty form again.

jellyfin-plugin-settings-3

Context

Hardware: Old laptop
YunoHost version: 11.2.11.3 (stable).
I have access to my server: Through SSH | through the webadmin | direct access via keyboard / screen | ...
Are you in a special context or did you perform some particular tweaking on your YunoHost instance?: no
Using, or trying to install package version/branch: jellyfin Version : 10.8.13, opensubtitles plugin 19.0.0.0

Steps to reproduce

log in jellyfin wit an admin account
go to the DashBoard
go to the 'Plugin' tab
click on the Open Subtitles plugin button or on the three dots buttons
face your screen with dismay.

Expected behavior

the plugin's setting form is correctly displayed and whatever credential you fill in is used by the plugin to get the subtitles

Logs

there is nothing relevant in jellyfin's logs, but the browser console is yelling that :

Loading failed for the module with source “blob:https://jellyfin.[mydomain.com]/824c666a-564d-4ca2-a75b-12168c01354f”. [index.html:1:1](https://jellyfin.[mydomain.com]/web/index.html#!/configurationpage?name=opensubtitles)
Content-Security-Policy: The page’s settings blocked a script (script-src-elem) at blob:https://jellyfin.[mydomain.com]/824c666a-564d-4ca2-a75b-12168c01354f from being executed because it violates the following directive: “script-src https: data: 'unsafe-inline' 'unsafe-eval'” [main.jellyfin.bundle.js:2:254778](https://jellyfin.[mydomain.com]/web/main.jellyfin.bundle.js?d5f64bca077b6d6aaf33)
Uncaught (in promise) Error: Failed to import: https://jellyfin.[mydomain.com]/web/configurationpage?name=opensubtitlesjs
    onerror https://jellyfin.[mydomain.com]/web/main.jellyfin.bundle.js?d5f64bca077b6d6aaf33:2
[main.jellyfin.bundle.js:2:254433](https://jellyfin.[mydomain.com]/web/main.jellyfin.bundle.js?d5f64bca077b6d6aaf33)

note that I recently had an issue with another app (galène), that was blocked by nginx's content security policy, I had to edit security.conf.inc manually and add connect-src ws: wss: 'self'; to the more_set_headers "Content-Security-Policy : […] line (see https://forum.yunohost.org/t/galene-couldnt-connect-to-wss/29196/6 for more details)

YunoHost-Apps / jellyfin_ynh