What's on the underside of the leaf

Hi,
I'm completely new to fishkeeping. I have a 25 litre cold water tank with 9 celestial pearl danios in..... nothing else. Yesterday I noticed something on the underside of two of the leaves of the live plant. Does anyone know what it is. I thought it was eggs, but I'm just guessing.
Many thanks

Looks like air bubbles trapped under the leaf.

I see. My daughter wasn't sure if she could see something moving, but guess it could have been reflections. Thankyou for your help.

Turn the leaf over. If they float to the surface its just trapped air.

Good idea. I'll do that.
Think daughter was wishful thinking!