[Hosted Che] Webviews not working correctly

Describe the bug

My environment has problems viewing pages containing webviews. When I start the workspace, the welcome page is not shown correctly. Even when reloading the page, I still get an error. The problem is visible also when I install some plugin using webviews and I try to use that. (see pictures sections for gifs). I tried with Google Chrome v. 81 and 84, both “normal” and incognito window. I was not able to reproduce with Firefox v. 78 (both normal and incognito). I tried different users on different clusters (2, 2a). I tried to clear cache, restart the browser, restart the whole PC - the issue is still the same.

Che version

• latest 7.16.0
• nightly
• other: please specify

Steps to reproduce

1. Log in to che.openshift.io
2. Click on one of workspaces examples.
3. Wait for workspace to start.
4. Wait for welcome page (Eclipse Che tab). (for testing the plugin using webviews:)
5. Install vscode-didact plugin.
6. Restart workspace to enable the plugin.
7. Open file tree.
8. At the bottom, click DIDACT TUTORIALS -> Didact
9. Click on play icon next to Didact Demo.

Expected behavior

Web pages should work correctly.

Runtime

• kubernetes (include output of kubectl version)
• Openshift (include output of oc version)
• minikube (include output of minikube version and kubectl version)
• minishift (include output of minishift version and oc version)
• docker-desktop + K8S (include output of docker version and kubectl version)
• other: (please specify)

Screenshots

Welcome page reload don’t fix the problem

Plugin using webviews not working

Installation method

• chectl
  • provide a full command that was used to deploy Eclipse Che (including the output)
  • provide an output of chectl version command
• OperatorHub
• I don’t know Hosted Che

Environment

• my computer
  • Windows
  • Linux
  • macOS
• Cloud
  • Amazon
  • Azure
  • GCE
  • other (please specify)
• other: please specify Hosted Che

Eclipse Che Logs

When trying to reload the page, those logs appear in console and network tab:

[ibuziuk]

@sunix for now I just document it to the Troubleshooting instructions - https://github.com/eclipse/che-docs/pull/1641

[ibuziuk]

The sso incident for the iframe issue has been created. Will update the issue once there will be updates from the sso team