White screen after updating from 5.37.0 to 6.3.7

Summary
After upgrading our server from version 5.37.0 to 6.3.7 people getting white screen after they reload the Mattermost desktop app. Mobile apps working correctly

Steps to reproduce
Following the instruction here to upgrade from 5.37.0 to 6.3.7: Upgrading Mattermost Server — Mattermost documentation
No errors in the install process

Observed behavior
After the server restart, people got the message to restart the app because of a new server version. After that restart there is only a white screen. Dev console shows the error “ERR EMPTY RESPONSE” from a main file. The apps on our mobile phones still working and have a connection to the server.

What Mattermost desktop app version are you on?
What OS and version are you on?
Do you see any developer console errors?

What Mattermost desktop app version are you on?

  • We having different version installed for example 5.0.1 and 5.0.4. On my Macbook it’s kinda special because I have no errors at all and can login. I have the 5.0.4. with a white background screen and blue loading icon. My colleages that can’t login have also 5.0.4. but with a blue background screen and white loading icon. I don’t know if that helpful.
    edit: Now I can’t login too.

What OS and version are you on?

  • macOS Monterey Version 12.1 and 12.3.1. Other Macbook running on macOS Big Sur. Also on Windows 10 with the client versions 4.6.0 and 5.0.5 no connection.
    On ios and Android mobile phone everything works fine.

Do you see any developer console errors?

  • The only dev console errors I can see are:
    main.8f9f284030e654ec79db.css:1 Failed to load resource: net::ERR_EMPTY_RESPONSE
    main.d54d4ec050258613a991.js:1 Failed to load resource: net::ERR_EMPTY_RESPONSE
    manifest.json:1 Failed to load resource: net::ERR_EMPTY_RESPONSE
    Besides these I don’t see any other, even in the server logs.
    edit: Now I have additional errors in my console in Mattermost:
    ChunkLoadError: Loading chunk 977 failed. main.d54d4ec050258613a991.js:2
    Uncaught (in promise) ChunkLoadError: Loading chunk 977 failed. main.d54d4ec050258613a991.js:2

Edit:Another question: Do I need to complete the steps that are under v6.0 database schema migration too? I didnt’t see these the first time.

Another thinng I noticed: After approximately one day I see the Mattermost server in the client. When I delete the cache it’s again a white screen and I have to wait. And again: on the mobile apps it’s working all the time, so it can’t be a server/database error right?

Right now, it’s working again but for example if I want to change something in the backend (for example activate or deactivate plugins) I’m getting the following error message: client4.ts:3764 PUT https://chat.domain.tld/api/v4/config 500 (Internal Server Error)