You know what…that is a very good point and I never thought about that. If I understand you correctly that if someone has a light or white coloured logo for the desktop version within the left or right sidebar, when viewing mobile, the logo is hard to see or blends in with the white page?
If this is what you mean, you have a good point. Confirm this and what I will do is recode the theme so that there are “two” logo uploads, one for the sidebar and another logo upload for the mobile. This will actually be a major update to the theme, as well I will have to do this for the Lite version of the theme too. This will take me about a day or two.
Of course, this would mean everyone needs to logo versions. Perhaps if in mobile view, I put the mobile logo view in a colour background that was the sidebar colour? This might be better…what is your thoughts on this instead of two logo uploads?