Nextcloud 19 collabora and CODE serveur connection

Hello nextcloud community.
I have a fresh install of nextcloud19 on OVH mutualised server.Everything work fine, except collabora.
When I go to setting, I select CODE server, but I have a red circle with a refused connection to CODE server.
Apps CODE server is installed and activated.
Nothing in nextcloud logs ?
any idea to the origin of the problem ?
nota: I am still in http, not yet https.

I am now in https, same problem

Could it be that you need to open another port that the code server is running on?

Im not sure about the code server, but i think i the past it had to run on a different port? Sounds like yours is running on a different port as well, and the firewall blocks it?

Thank you for your answer. How can I check in the parameters of nextcloudwitch port is used by code server ?There is no parameter pn the CODE server line in “parameters”
This nextcloud is hosted on a mutualised server, I dont have access to ssh.

I have find some logs (when trying to modifiy a document
It is a WOPI and getUrlSrc problem.
I try to find similar problem on the blog

I only find entries in the blog where CODE is installed form container, or from an other vhost, not when installed by using the application from nextcloud administration.
I cont find documentation on how it is installed, and if it is possible to install it on a mutualised server with very few configuration possibility.