opacity of a list box

hi again

changing list boxes  opacity does not applied to background image. Is it proper? Took a look at your source code of button-opacity vs listbox opacity and see that something
like 
         "getRenderer()->m_backgroundTexture.setColor({255, 255, 255, static_cast<sf::Uint8>(m_opacity * 255)});"

is missing.

The line is indeed missing in ListBox and ComboBox, updated on github.
I found it strange that I would have introduced a bug like that during the opacity rewrite, but after looking through the changes it seems like they just never supported transparency at all for their background image.