A display-saving or night-brightness preference may deliberately change the clock's appearance while the oven is idle.
What the observation means
A blank standby screen is different from power disappearing during cooking. Some models wake when a normal control is touched; others have a clock-display setting. Check the owner's settings menu rather than assuming that the supply is intermittent.
A useful next step
Record whether the cooking programme and other functions remain available. If the entire appliance loses power unexpectedly, especially with tripping or burning smells, stop using it and arrange assessment. Do not change wiring because a standby clock no longer remains illuminated.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.