The requested state can change
MDN documents a promise-based screen wake-lock request and a sentinel that can be released. An application should report an acquired lock only after the request succeeds. A button labelled Keep screen on does not by itself establish that the system granted the request.
Imagine a viewer starting a long lesson. The page requests a lock and displays a confirmed state. Later the viewer leaves the active page and the lock is released. If the interface continues claiming it is held, the label is stale even if the original request once succeeded.
Visibility and system conditions matter
The documented API restricts acquisition to active documents and describes automatic release when the document becomes inactive. A later return can require a fresh request if the task still needs it. A refusal can also reflect system conditions, so the application should preserve the error rather than claiming a service outage.
Do not equate a wake lock with network access, audio routing or media authorisation. Keeping a panel awake does not download the next segment or renew a subscription. If video stops while the screen stays lit, that is a separate outcome from the screen dimming or locking.
Use a bounded viewing decision
A sensible application releases an acquired lock when the relevant activity ends. Viewers should retain control over battery use and ordinary device behaviour. This reference does not recommend disabling system protections or changing sleep settings globally to mask an unidentified playback issue.
For a technical report, record whether the request succeeded, whether a release event occurred, what action changed visibility and whether media itself continued. Those observations can isolate a lifecycle defect without guessing about the power subsystem. Test the actual supported environment before promising that a web player will keep every phone, tablet or television display awake.
Questions about this guide
Is an acquired lock permanent?
No. It can be released by the application or system.
Does keeping the screen on guarantee media delivery?
No. Screen state and playback dependencies are separate.