Stop WPF TextBox from growing - wpf

Question

I have spent two hours researching how to avoid that my WPF TextBox Control grows when a long text has been typed in, but I have not been able to do it, even I have read some answers about it like these ones:
stopping-wpf-textbox-from-growing-with-text
wpf-allow-textbox-to-be-resized-but-not-to-grow-on-user-input
wpf-how-to-stop-textbox-from-autosizing
My code is the following:
<Grid>
<TextBox Margin="6,6,8,28" Name="textBox1" AcceptsTab="True" TextWrapping="Wrap" VerticalScrollBarVisibility="Visible" AcceptsReturn="True"/>
<CheckBox Content="Case sensitive" HorizontalAlignment="Left" Margin="7,0,0,2" Name="checkBox1" Height="16" VerticalAlignment="Bottom" />
</Grid>
One thing that I tried was:
MaxWidth={Binding ElementName=MyGrid, Path=ActualWidth}
But it did not work for me.
I also tried to add the following property to the Grid:
ScrollViewer.HorizontalScrollBarVisibility="Disabled"
Or
<Border x:Name="b" Grid.Column="1"/>
<TextBox Width="{Binding ActualWidth, ElementName=b}" ....... />
But it did not work either.
I need my control to grow when the user stretches the window, but not to when a long text is inserted.
Do you have a different answer for this problem that I might try?
UPDATE!
I have noticed something very strange: If I stretch manually the window, the textbox stops growing when a long text is inserted. That's fine. But I need to achieve this without having to stretch the window every time I run the program

Answer 1

Remove TextBox border and put it into ScrollViewer.

Answer 2

Try to do next:
<ScrollViewer MaxHeight={Binding ElementName=MyGrid, Path=ActualWidth} BorderThickness="0">
<TextBox Margin="6,6,8,28" Name="textBox1" AcceptsTab="True" TextWrapping="Wrap" AcceptsReturn="True"/>
</ScrollViewer>