No connection to brrowser via direct connection or reverse proxy - error message : Service Unavailable

Hi Everyone,

I'm trying to access my database with Chrome browser (and I've also tried with Edge and Firefox with the same result) and i'm continuously running into the same error : ServiceUnavailable: WebSocket connection failure. Due to security constraints in your web browser, the reason for the failure is not available to this Neo4j Driver. Please use your browsers development console to determine the root cause of the failure. Common reasons include the database being unavailable, using the wrong connection URL or temporary network problems. If you have enabled encryption, ensure your browser is configured to trust the certificate Neo4j is configured to use. WebSocket readyState is: 3

I've checked on the forum, noticed that some of the post dosent contain any answer or informations and others with answers.
So I've tried them...yes, all of the answers found here have been tried but none of them are working by my side.

I thought it was because I was using Nginx as a reverse proxy, so I've tried with Apache...and firstly directly on neo4j browser.

But...nothing new

I've also tried to connect to neo4j with cypher-shell...and it work...good point.

I'm on Google Cloud Platform and the ports 443, 7687, 7474 and 7473 are already opened.

I don't know what I can do to make the connection through web browser works...So if you have an idea or if you need to check on my config files, don't hesitate to ask.