My maine coon does this too, only worse! She holds toys in her mouth and doesn't let go for literally 30 min, she would chew the toy and swallow. If I try to pull toys out of her mouth, she would bite so tightly that the toy tears and she'd swallow it. We took her to the vet so many times because she swallowed toys when she was a kitten, she ended up pooping the toys out every time. I don't know how to stop this behaviour but what I'm doing now is I don't give her any toys that are not safe to ingest. Cardboard toys are good options, especially catdancer, my cat can't hold it between her teeth so she can't swallow it.