The answer to 'light fixture burning smell' is that a burning smell coming from a light fixture is a sign of a serious electrical issue that requires immediate attention. This could be caused by a variety of problems, such as a short circuit, overloaded circuit, faulty wiring, or a malfunctioning fixture. The smell indicates that the fixture is overheating and could potentially start a fire if not addressed promptly.
If you notice a burning smell from a light fixture, turn off the power to that circuit at the circuit breaker immediately. Do not attempt to use or troubleshoot the fixture further. This is a job for a professional electrician, as they have the expertise to safely diagnose and repair the issue. Trying to fix it yourself could be extremely dangerous and lead to further damage or even a fire.