ad9e44e92a
The rec-arm circle diameter is given by 0.5 * min (width, height). For mono tracks the diameter is limited with the height of the track. When more channel meters are visible the height increases and the rec-arm circle grows. The solution here is to constrain the rec-arm button width to its minimum and not grow to have the same width as other buttons. This also changes the default meter-height so mono and stereo tracks have the same height (with default scaling).
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