Your laptop is sticky because it was covered with rubber that melted after years and alcohol or other cleaning products can't deal with it?
tl;dr buy plastic cleaner foam
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| Doesn't have to be this one. |
You have to shake the can vigorously and spray it. There's a large volume of foam usually, so don't spray it for too long, you'll overdo it. You can spray the keyboard if you want, however I don't guarantee that it won't break it.
After this procedure, wait a bit until the foam starts to reduce its volume. Take a sponge with sharp edges or something similar, and wipe the rubber off vigorously.
Photo taken before cleaning - some sort of crumbs stuck to the surface. It's hard to capture this layer of rubber in the photo, because you can only feel it under your fingers and nails.
A little warning.
In the second photo, the paint on the left half has started to come off. I assume that the reason is that the rubber has completely melted there, or melted into the paint, which is why the detergent removed the color. I put stickers there and it was actually the first Dell from this series that did that to me. I had a few Latitude E6230s, and there the layer with the rubber came off without the paint, so aesthetically it's fine.
Additionally, you can experiment with aftershave, however be extra careful with that, since it's literally water.
I hope I saved someone's laptop from being unpleasant to use.