Middle Mouse turns on Perspective Blender 2.8 is really great. Many thanks for the rework of the UI :)

I have one "tiny" problem. I am working mostly in orthographic view and I rotate a lot during modelling. Every time I rotate I have to press the middle mouse. This press activates perspective view what is annoying especially if zoomed in. (It only activates, it doesn't deactivate). I didn't find how to disable this in the keymap.
If Auto Perspective is set in User Preferences > Navigation ...



.. then the view will revert to perspective on leaving any of the standard orthographic views.