I'm doing a bit of archviz for a buddy's bathroom remodel, and I want the windows and reflective surfaces to show a background without it darkening the scene. I think in 2.79 you could set the object to not cast shadows, but that seems to have been removed. I know I could use view layers, but A. I'm very confused by them, despite them ironically being made to supposedly be easier than the old method, and B. Next to a window is a glass plane that reflects the environment, and I don't know how I'd composite that in. I've also added in an external ground plane to get some ground color bounces.
Of note is the image with the background is blocking a lot of sun and sky light, so it's darker overall.