A thin layer of petroleum jelly on a bulb's metal threads keeps heat and moisture from corroding it in place, so the next time it needs changing, it twists right out.
The Trick That Keeps Bulbs From Fusing to the Socket

Hello Neighbor! Last week my porch light bulb would not budge when I went to change it, no matter how hard I turned it.
My sister-in-law Carol, who lives two doors down, came over and reminded me of a trick her dad always used: a thin coat of Vaseline on the threads before screwing in a new bulb.
I did every bulb in the house that same afternoon, and after a lot of wiggling and tapping, I finally got the stuck porch bulb loose too.
Be Well,
Anisa
Rub Vaseline on Light Bulb Threads Before You Screw Them In
How to Do It
Make sure the fixture is off and the bulb and socket are completely cool, then dab a small amount of Vaseline onto a cotton swab or your fingertip. Rub a thin coat along the metal threads of the bulb only, not the glass or the socket itself, then screw the bulb in as usual. The thin layer keeps it from fusing to the socket over time.
More Ways to Use It
The same trick keeps garden hose connections and shower rod ends from sticking too. A dab on a squeaky hinge will quiet it until you get real oil on hand.
Ask the Genius: Is Vaseline Safe That Close to a Light Fixture?
"Is Vaseline safe to use that close to a light fixture, will it get hot enough to smoke?"
Yes, a thin coat on the threads only stays far enough from the hot glass and filament to be safe. Just use a light touch, a thick glob is messy and unnecessary.
Got a handy tip of your own?
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