The main problem seems to be that the filesystem permissions in the application containers, especially /client/plugins, /plugins and obviously also some parts below /data do not seem to be writeable by the pods and someone came up with the idea to start a sidecar container to fix that during initialization, but I don’t believe that this is the only way to fix permission issues. Not sure what needs to be done here in order for the permissions to be set correctly in such a deployment scenario and since you’re experienced with the k8s environment I pinged you for help.
Thank you @michaelkoelle for the workaround. Unfortunaly it didn’t work for me, my initcontainer has not the right to modify permission of the folder /client/plugin. I hope this issue will be resolved by mattermost. I encounter the problem since I started the depolyment in my compagny with version 7.7.0