Can't remove padding of custom ContentDialog

Describe the bug I want to remove the padding of a subclassed ContentDialog. Setting ContentDialogPadding to 0 is not working.

Steps to reproduce the bug

<ContentDialog
    x:Class="Namespace.AuthDialog"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    Style="{StaticResource DefaultContentDialogStyle}"
    mc:Ignorable="d">

    <ContentDialog.Resources>
        <Thickness x:Key="ContentDialogPadding">0</Thickness>
    </ContentDialog.Resources>

...

</ContentDialog>

Expected behavior

Actual behavior

NuGet package version: [Microsoft.UI.Xaml 2.6.1]

Windows app type:

UWP	Win32
YES

Windows version	Saw the problem?
Build 19043.1165	Yes
October 2020 Update (19042)
May 2020 Update (19041)
November 2019 Update (18363)
May 2019 Update (18362)
October 2018 Update (17763)
April 2018 Update (17134)
Fall Creators Update (16299)
Creators Update (15063)

Device form factor	Saw the problem?
Desktop	Yes
Xbox
Surface Hub
IoT

[tipa]

@michael-hawker thanks! Yes, using the adjusted template in my custom ControlDialog seems to work

[michael-hawker]

I plan to submit a fix for #424 on a future dev stream of mine and try and investigate #4247 too. I was able to build the WinUI repo locally and run their test app. Just trying to get our Toolkit release together and working on our last feature there, so don’t know timing yet.

@tipa you can copy the style and test the suggested fix in #4247 and see if that works, knowing that would be helpful.