I belong to a pottery collecting chat group and asked them recently how to display a 19" ceramic poodle without having my cats and/or dogs knocking it over.
Several people recommended Museum Putty, there is also a Museum Wax and a product that is invisible to use on glass shelves. This stuff is wonderful! I can now put a lamp on a table and the cats can't knock it over!
My poodle sits robed in glory in my living room (they are all afraid of it) and I don't worry about it crashing to the ground when the cats visit the window.
Just google museum putty and you'll find the various places that sell it.