Do we all know about
this?
For what it's worth, I think he's making a web. But looking gooood doin' it.
They are so cute.
He's not making a web, he's trying to attract the attention of a lady spider. Jumping spiders don't live in a web the way garden spiders do.
He is laying down some silk. They tend to lay down a line as they go along. Maybe so they know the way back if they need a fast retreat, or an anchor if they have to jump for it. I'm not really sure.
The silk could also be another way of identifying himself to the female.
I know my male tarantulas will lay down a trail when they cautiously approach the female. They also tap/drum with their feet to let her know they are there, and try to get her attention.
If the female is not in the mood, the male needs to book it out of there fast, because she will make lunch out of him.