I have a Xamarin.Forms UWP app with a <ContentPage.ToolbarItems> defined with two toolbarItems.
In UWP this toolbar renders but displays an extra (or default) button with 3 dots that expands but does not contain any buttons. I want to remove this extra button.
I found some references on this problem but they didn't work for me:
As per the answer in the link that you mentioned in your post, did you tried to put below code in your App.Xaml of your UWP project:
<Application.Resources>
<x:Double x:Key="AppBarExpandButtonThemeWidth">0</x:Double>
</Application.Resources>
Since Windows 10 Anniversary Edition ( so your project's min version is 14393 and target version is 14393 or greater ) there is a property on the CommandBar that you can use to toggle the visibility of the 3 dots/more button.
It's call OverflowButtonVisibilty and the docs are here: https://docs.microsoft.com/en-us/uwp/api/windows.ui.xaml.controls.commandbar.overflowbuttonvisibility
You can set it like so
<CommandBar OverflowButtonVisibility="Collapsed"></CommandBar>