Note that `Ref`s and `Name`s are cached globally[1], since that helps reduce object creation (a lot) during parsing.
That cache will be cleared after a period of inactivity in the viewer[2], which is why those primitives cannot *safely* be compared with just `===`/`!==` and also (partially) why abstractions such as `RefSet`/`RefSetCache` are necessary.
Currently `deepCompare` doesn't handle `Ref`s and `Name`s correctly, which may lead to future *intermittent* bugs in any code using the `deepCompare` helper function.
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[1] This applies to `Cmd` as well, however that doesn't matter in the context of this patch.
[2] Currently, and for more than a decade, set to 30 seconds.
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