Bug report

I am upgrading some code to PHP8.2 using PHPStan to discover possible issues.
I have a class that defines a __set and __get magic function, as well as the magic __isset function.
If I access or write any properties on this class, no errors occur, but if I use
if (isset($instance->x))
I get:
Access to an undefined property class::$x

Code snippet that reproduces the problem

I tried but I get a different unexpected error.

https://phpstan.org/r/d253ad7c-9651-44b4-bce9-b95358d812c2

Expected output

No error

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