I believe this might be the thread that Gaspershooters is referring to. https://forums.wincustomize.com/364637
Of the things mentioned in there:
- Opus no longer adds anything to the titlebars (as Neil says) so that's a non-issue now. (And WB skins Opus's titlebars anyway, so it's a moot point either way. 
)
- The resize grip on the glass status bar will look wrong with some themes, since Opus assumes the grip will be drawn on top of the background but some themes draw a solid square with the grip inside it. Users can turn off the glass status bar option in Opus if they are using a theme where that causes a problem. (Or even better update the theme to draw resize grips like the standard themes all do ).
One thing I noticed myself:
- While testing WB with dopus.exe renamed to test.exe, I also noticed an issue with one theme where the menus had extra lines around each item. We can fix that (and any similar issues).
It'll actually be really useful if WB treats Opus normally as it'll allow us to test our code against a wider range of themes than the ones that ship with Windows, since the Windows documentation about how you actually use the theme parts is non-existent, leading people to have to guess. For example, the menu issue I just mentioned is because Windows stretches the menu-item background across the entire menu, while Opus draws it for each menu item. Since the standard themes all have solid colours for those theme elements it's impossible to tell the difference between one arbitrary choice and the other. (It seemed like a sensible choice, too, since there is a separate theme element for drawing the menu border, which could've included the menu background if it was meant to be stretched across the whole menu.)
