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Upgrading Architect 2.0 project to 2.1 removes preventHeader
When our projects were upgraded to Architect 2.1, the preventHeader attribute was erased from the ext components across all of our files. Every location that had a preventHeader requires you to go to the component, search for header, enable header, then disable header to get the same functionality.
This means that a manual process has to happen where exports pre 2.1 upgrade are gone through to look for every instance of preventHeader, then setting "header" to false in that component by hand.