EventSetter is lost.

[CreateAndInject]

Original:

<Window x:Class="WpfApp4.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp4"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Window.Resources>
        <Style x:Key="style1" TargetType="{x:Type Button}">
            <EventSetter Event="Click" Handler="Button_Click"/>
        </Style>
    </Window.Resources>
    <Grid>
        <Button Style="{StaticResource style1}"  />
    </Grid>
</Window>

ILSpy:

<Window x:Class="WpfApp4.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local="clr-namespace:WpfApp4" Title="MainWindow" Height="450" Width="800">
  <FrameworkElement.Resources>
    <ResourceDictionary>
      <Style x:Key="style1" TargetType="{x:Type Button}" />
    </ResourceDictionary>
  </FrameworkElement.Resources>
  <Grid>
    <Button Style="{StaticResource style1}" />
  </Grid>
</Window>

<EventSetter Event="Click" Handler="Button_Click"/> is lost.