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Image services prevent offline map areas from being downloaded in ArcGIS Collector and ArcGIS Field Maps – limitation is undocumented. Only in a custom app this can be resolved with the newest version Javascript API. This will not be resolved yet at ArcGIS Enterprise 10.9.x, and ESRI AU has submitted it to ESRI Inc. as  defect for development consideration. See https://support.esri.com/en/bugs/nimbus/QlVHLTAwMDEzNzUxNA==

ENH-000136006 [Enhancement] - for external Spatial Portal users in ArcGIS Pro 2.8

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This bug relates to ArcGIS Pro 2.7.x Users that are logging into Spatial Portal via QGov account (identity.qld.gov.au) using their Queensland Government accounts cannot authenticate.

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