Activity details field longer than 64k crashes exports – temporary table column is text when actual column is longtext
To reproduce, create an activity with a details field longer than the length limit of a text column (this came up in a ~95kchar long column for us), then try to export it.
I couldn't see off hand why this would be – suspect there's an edge case CRM_Export_BAO_Export(Processor)->sqlColumnDefn that's being handled incorrectly.
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