Leaving the light on in your fridge for an extended period is unlikely to cause any significant harm to the fridge itself. Modern refrigerators are designed to handle the light being on for extended periods without any issues. The light bulb used in refrigerators is usually low-powered and doesn't generate much heat, so it won't have a significant impact on the internal temperature.
However, there are a few considerations to keep in mind:
Energy consumption: Leaving the light on unnecessarily will lead to increased energy consumption, albeit it's relatively small compared to the overall energy usage of the fridge. If you're concerned about energy efficiency, it's best to turn off the light when not needed.
Light bulb lifespan: Frequent switching on and off can sometimes shorten the lifespan of a light bulb due to the stress on the filament. However, modern LED bulbs used in refrigerators are quite durable and should last a long time even with constant use.
Battery-powered fridges: If you have a portable or off-grid fridge that operates on battery power, leaving the light on for an extended period could drain the battery faster than necessary, affecting the fridge's overall performance.
In summary, leaving the fridge light on won't likely harm the fridge, but it's still a good idea to turn it off when not needed to save energy and prolong the lifespan of the light bulb.