https://www.facebook.com/Catmuseumkrakow/photos/a.343176466620675/950394972565485
such a big sign, if its open I have to start wearing glasses I guess :p  

jokes aside I checked Tripadvisor and the last rewiew (july 2022, translated from Dutch) says:
"The museum no longer exists. It's that I had the address and seen pictures of what the building looks like from the outside, otherwise I wouldn't have been able to find it. There is also no reason to assume that the museum will return, there is now a shelter for Ukrainians and a Covid research center."