Squirt made a bubble nest! : )
Male betta fish make nests by blowing bubbles when they are ready to mate. (the eggs go into the bubble nest).
It signifies that they are happy and healthy.
So here is a picture of Squirt's creation:
Isn't it huge?
(I only got the picture after I took water out of the tank for a cleaning, I didn't notice the bubble nest till I saw it sliding down the side of the tank.)