She didn't switch to another language in Docker.

I changed the contents of the title.html file to Hungarian and the main page still says Join Meeting. Where and which file do I have to rewrite in order for the welcome text to appear in Hungarian?

Jitsi localization is done by editing language files. That would be lang.main-hu.json for you. I have no idea about changing this file in docker, I don’t use it, but on a Debian install just editing the file and reloading the browser is enough to see the new version.
How about updating the file in Jitsi-meet for every user using your language ? If you need guidance it can be provided on this forum.

I only have the countries-hu.json file, and only the countries are translated in it. There is no other text in it. Do you have any other ideas?
What’s more is the main-hu.json I didn’t find the Meeting text here.

I don’t quite get what you are meaning by

and

if you don’t find the string in the main-hu.json file that’s some indication that you have a main-hu.json file no ?

Anyway, the string you want is not in the main-hu.json because it’s badly outdated. There are many strings missing from this file, and it’s needed to add them.

What exactly should I add to the contents of the main-hu.json file?

The missing strings are in the main.json file. You can add them by hand if you are really liking suffering, or automatically, I know of 2 ways of doing that:

  • the official way: install npm, git, git clone the jitsi-meet repository, run npm install and npm-update-translation.js as stated in lang/readme.md, then after editing the file run resources/lang-sort.sh and then upload the result to github as a PR

  • my way: see here

Unfortunately, this is difficult for me in this form as you have described it. I’d love to write it in the main.json file, just give me an example.

no, it’s useless it’s compiled in the code, changing it will do nothing.

Thank you very much, I am reading documentation yet.

Solved.