Inspect the actual background arrangement
The current MPV Shim README describes tray/background behavior and a headless configuration that shows a ready-to-cast screen. It also cautions that headless mode is not a security feature. Check those choices in the installed build before applying instructions from an older release.
Preserve the original configuration and identify how the process can be stopped. A machine remaining available after a window closes can be intentional. Record that policy so another user does not assume a closed window means the server session has ended.
Test one state at a time
First test ordinary background behavior: close the visible window through the intended control, then inspect target availability from the authorized sender. Record whether a new sample can be sent and whether stop works. Keep the same account and server throughout.
If a ready-to-cast-only interface is required, apply the documented setting separately and inspect the local screen. Verify that casting and playback behave as expected while the ordinary library view has the intended availability. A configuration file someone can edit is a different control boundary from a local interface choice.
Retain a recoverable ordinary setup
After the comparison, choose the intended everyday policy and verify a normal restart. Keep the management route and credentials protected according to the actual device’s role. Avoid leaving an unexplained target active on a shared workstation after the demonstration.
The expected outcome is predictable background and local-interface behavior for a particular build. It does not encrypt saved accounts, create a managed kiosk or prevent an administrator with filesystem access from changing the configuration. Keep those separate requirements explicit rather than inferring them from the word headless.
Questions answered
Does headless mode provide complete account isolation?
The project explicitly treats it as a convenience, not a security feature. Assess actual device and filesystem access separately.
What should be tested after closing the window?
Check whether the intended target remains available and whether authorized playback and stop still work. Record the chosen background policy.
Sources & further reading
Official references for the subjects discussed. Service terms and device software can change.