Viewports on Open GL now show me a solid white background, not transparent as before, how can I remove that?

[Acosta]

Have been using VW for years, many times I overlay different viewports, but now when render viewports on OpenGl they come with a solid white background, not transparent anymore, how can I deactivate this?

 

Thanks 

[Tom W.]

Does the VP have a fill in the Attributes Palette?

[Andy Broomell]

If setting the Attributes Palette Fill to None doesn't fix it, the second thing to check is that the Viewport doesn't have a RW Background applied in the OIP. For example, the background called "HDRI White" might look the same as a white fill, but the solid white would be coming from the background, which would have to be removed (set to 'None') to get the alpha transparency back.