In case you change a variable type from one class ref to another class ref blueprint pin connections working on this class ref variable.
This will lead to silent bugs which are not catched by the blueprint compiler.
Those disconnected bugs are hard to detect.
The expected behavior would be to not break pins and instead issue compiler errors which have to be fixed.
This is not true in any case. It would only be true for reference pins. And another disadvantage is that you have to figure out on your own which pins broke and what is the output->input relation.
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