Opening idml from CC2021 crashes CC2020 but not CC2019 and earlier
When I save file as an idml from CC2021 I cannot open it in CC2020 as it crashes. CC2019 and earlier can open idml files from CC2021. It seems to be an issue only with CC2020. I've managed to open a 1 page blank document with CC2020 from CC2021, but anything that I've worked properly on crashes when the idml is opened in CC2020. I've attached an example.
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