Windows Runners: Document "session 0" restrictions (screen resolution statically set to 1024x768)
Problem to solve
Windows Services isolate running processes to a special session, "session 0". This session is subject to more restrictions.
Specifically, in customer issue ZD-562057, we discovered that the screen resolution for UI applications is restricted to 1024x768
Further details
I've tested this against Windows Server 2022 (virtualized, display resolution 1280x800), in the following scenarios:
- Running as service, in the
NT AUTHORITY\LOCAL SYSTEMcontext: https://gitlab.com/customer-issue-reproduction/zd-562057/-/jobs/7686846526 - Running as service, in the context of a local user: https://gitlab.com/customer-issue-reproduction/zd-562057/-/jobs/7686826122
Both scenarios returned a resolution of 1024x768.
The only way to achieve the "native" resolution was to get rid of the session 0 isolation entirely, by running as a regular process in session 1: https://gitlab.com/customer-issue-reproduction/zd-562057/-/jobs/7687000162
This is not a good workaround, from a security perspective, and I wouldn't recommend it in any official capacity.
Proposal
From a Support perspective, I would stay away from recommending any workarounds, at all. This appears to be an intentional platform limitation imposed for security reasons.
However, I would like to point this out in the docs.