☕TL;DR In Kamua, you can very easily remove black Bars from a video, for any Aspect Ratio. You can remove them from the entire video, or from individual Clips.
Tag: Black Bars
☕TL;DR The Auto Aspect Ratio is determined either by the Aspect Ratio of the the first video added to the Timeline or by the dimensions of whichever video has the smallest black bar region, once black bars have been removed.