Focus on something up close in your dream, like the texture of a wall or table, it’ll pull you back into the dream. Works for me!
The other suggestion is to spin around, but I did that to stay in a dream once and noclipped through the floor. Which woke me up.
Man I watched that whole video, it has nothing to do with the headphone jack. It’s about how fairphone releases repair schematics. The title is clickbait, he still says “the removal of the headphone jack is still bullshit and I stand by that, but they sure do release schematics which is nice”.