Is there a full list of types converted to heap types? There may be other issues related to differences between heap and static types.

1. Static type with tp_new = NULL does not have public constructor, but heap type inherits constructor from base class. As result, it allows to create instances without proper initialization, that can lead to crash. It was fixed for few standard heap types in issue23815, then reintroduced, then fixed again in issue42694. But it should be checked for every type without constructor.

2. Static types was not pickleable with protocol 0 and 1 by default. Heap types were pickleable by default, as result, you did not get error when pickle instances of newly converted types, but get an error when try to unpickle. It was fixed in general enough case in issue41052, but it is worth to recheck it for every converted type.