Use icon button style
MODIFY
WalletWasabi.Fluent/Views/Wallets/Receive/ReceiveAddressView.axaml
WalletWasabi.Fluent/Views/Wallets/Receive/ReceiveAddressView.axaml
</StackPanel>
<DockPanel MaxHeight="250" HorizontalAlignment="Center" Margin="0 0 -30 10">
- <Button Command="{Binding SaveQrCodeCommand}" ToolTip.Tip="Save" Classes="plain" DockPanel.Dock="Right" VerticalAlignment="Bottom" Margin="10 0 0 0">
+ <Button Command="{Binding SaveQrCodeCommand}" ToolTip.Tip="Save" Classes="plain icon" DockPanel.Dock="Right" VerticalAlignment="Bottom" Margin="10 0 0 0">
<PathIcon Data="{StaticResource save_regular}"/>
</Button>
<Viewbox HorizontalAlignment="Center" VerticalAlignment="Bottom" DockPanel.Dock="Left">

Use icon button style