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Incompatible with List Metadata navigation settings
The simplified ribbon control <PublishingRibbon:PublishingRibbon runat="server" /> utilized in these master pages appears to makes them incompatible with SharePoints OOTB Metadata navigation settings for lists and libraries.
To recreate this undesirable behavior, navigate to any list, select "List Settings" from the ribbon and then select the "Metadata navigation settings" options under General Settings. You'll get a lovely "Sorry, something went wrong"
error page. It appears the SPNavigation ContentPlaceHolder is missing.