Template 10 ellipsis collapsed error

[jameljoseph]

I inherited a program that was developed using c# and UWP that has errors that do not crash the program.

There are 2 control bars, a page header and page footer and the buttons are small enough that I do not need the ellipsis so I am trying to remove the ellipsis. The controls are from uwp template 10 (xmlns:Controls="using:Template10.Controls")

I am using the following XAML code:

<RelativePanel>

        <Controls:PageHeader x:Name="pageHeader" Frame="{x:Bind Frame}"
                             RelativePanel.AlignLeftWithPanel="True" RelativePanel.AlignRightWithPanel="True"  RelativePanel.AlignTopWithPanel="True" 
                             x:Uid="MapPageHeader" IsOpen="True" IsSticky="True" Height="40" DefaultLabelPosition="Right" EllipsisVisibility="Collapsed">

            <!--  primary commands  -->
            <Controls:PageHeader.PrimaryCommands>

                <AppBarButton x:Name="MapPageStationCommandButton" Label="" MaxWidth="100" Height="57" IsCompact ="True" Foreground="White" Icon="Map" Tapped="{x:Bind ViewModel.MapPageQuickButtons_Tapped}" x:Uid="MapPageStationCommand" VerticalAlignment="Bottom" />
                                </Controls:PageHeader.PrimaryCommands>

        </Controls:PageHeader>

The issue is I get the blue wiggly lines below the EllipsisVisibility="Collapsed" text with the explanation that "Unable to convert Collapse to an object of type Template10.Behaviors.EllipsisBehavior+Visibilities.

What does this mean?