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Animations start with a one-frame delay in Avalonia 11

See original GitHub issue

Describe the bug As of Avalonia 11 preview 1, controls are rendered for a single frame before animations begin. This is very noticeable if the animation is fading the control in by changing its opacity.

This does not happen in Avalonia 0.10.18

To Reproduce Paste the following XAML into a new window, run it, and click the button:

<Grid RowDefinitions="Auto,*">
    <ToggleButton Name="Toggle">Begin animation</ToggleButton>
    <Border Grid.Row="1" Background="Red" IsVisible="{Binding IsChecked, ElementName=Toggle}">
        <Border.Styles>
            <Style Selector="Border[IsVisible=true]">
                <Style.Animations>
                    <Animation Duration="0:0:1">
                        <KeyFrame Cue="0%">
                            <Setter Property="Opacity" Value="0.0"/>
                        </KeyFrame>
                        <KeyFrame Cue="90%">
                            <Setter Property="Opacity" Value="0.0"/>
                        </KeyFrame>
                        <KeyFrame Cue="100%">
                            <Setter Property="Opacity" Value="1.0"/>
                        </KeyFrame>
                    </Animation>
                </Style.Animations>
            </Style>
        </Border.Styles>
    </Border>
</Grid>

You will see the red border flicker on-screen as soon as the button is clicked.

Expected behavior When the control’s becomes visible its opacity is immediately set to zero, and no red border is drawn until the animation starts to raise the opacity value (after 900ms).

Desktop (please complete the following information):