has this been tested with browse mode and focus mode?

@seanbudd,
Yes, tested with both browse mode and focus mode.

I cannot call parent hash function here - I spent quite some time debugging this. Here is the reason.
RootProxyTextInfo is a subclass of TextInfo, which is a subclass of baseObject.AutoPropertyObject. The latter overrides

def __new__(cls, *args, **kwargs):
    ...
    self.__instances[self]=None
    ...

So it uses the object as key in a dictionary during a call to __new__, which in turn calls __hash__(). However at this time none of the fields of the object are initialized, since __new__ is called before __init__. So self.innerTextInfo doesn't even exist at this point. So using identity hash function seems to be the only possibility here.

BTW on a tengential note, there seems to be a fundamental problems with __eq__ and __Hash__ functions. It appears that Python expects the object to be immutable to support custom __eq and __hash__ functions, whereas TextInfos are mutable. I don't quite understand caching in AutoPropertyObject, but it seems to me that identity hashing with custom __eq__ function might not work as expected. Python expects that for any two objects a and b if a == b then it must be that a.__hash__() == b.__hash__(), but this assumption is violated at least with TextInfos. Please note that I am not breaking things in this PR, as this is the way it works in for example class UIATextInfo. Not sure if this might cause some hard-to-debug problems in the future.

@seanbudd, This PR is ready for review (sorry if I confused you by my previous comment). What should be the next steps to have this one and #13345 merged?

Does this handle also i.e. rows of different number of cells? See for example isue #2683.

This only forwards eq function for certain instances of TextInfo, it doesn't directly change any table-related behavior.