Everything seems to be normal even eating left overs.Except opening her mouth.
I had a male cat, arsalanArsalan, he. He used to eat every thing we ate i, e.eg., chocolate (later iI found out itsit's not good for them), banana, pomogranatepomegranate, apple, pasta, noodles, bread (yeast is not good for them),bhajji bhajji, kababskebabs, anything with masala andmassala or spicy (giving this rarely is okOK but not very often), etc. He disliked plain cooked meat, but Hehe liked it with a bit of salt and more flavour.
But, keeping the mouth open is not a good sign, she. She might have upper respiratory disease, which is very common in cats, itsIt's better to visit the vet. If treated early, it has alota lot more chances to be cured. Also, check if itsit's panting, and drinking more water than usual,pull. Pull her skin from inbetweenin between her shoulder blade, if. If it takes longer than usual to reach its original state, she might be dehydrated.