Repeat the exact transition
Choose a short familiar programme and keep the player, scene and display unchanged. Note whether the change occurs when the charger is removed, when battery-saving behaviour begins or only after switching to another screen. These are separate transitions with different clues.
Check that the display you are judging is the one selected in Windows Display settings. A laptop panel and an external television can advertise different capabilities. Having HDR available on one does not prove the other is receiving the same format.
Inspect HDR for the chosen display
Microsoft’s HDR guidance directs users to Settings → System → Display and the selected HDR-capable display. Its power section describes the battery trade-off. Review the available options on your PC rather than assuming every laptop exposes an identical toggle.
Keep a record of the original choice and compare the visual result before changing unrelated colour controls. A setting that increases battery use may suit a plugged-in viewing session but be undesirable on a long journey. Decide based on the actual use rather than treating maximum processing as universally better.
Keep the source and application in scope
An HDR-capable output does not prove that the current programme is HDR. The source, application and display path all matter. Microsoft’s separate Video playback settings guidance also identifies a participating-app scope; a control there should not be assumed to govern every desktop media engine.
If one browser changes but a standalone player does not, record the difference instead of declaring that Windows applies one rule everywhere. Use the player’s own status information when available, and avoid inferring the source format solely from the television’s picture mode name.
Report a display-state problem accurately
Include the laptop, display connection, app and whether the behaviour changes immediately with power state. Describe colour or brightness separately from pauses, blockiness or an error. Those symptoms can coexist but do not establish the same cause.
If playback is stable and the colour shift follows unplugging consistently, pursue the power/display path first. If the stream stops randomly regardless of power, start a network or media comparison instead. Restoring the charger can be a useful observation without being proof that the video account or internet connection is faulty.