I wanted to see the Track DSPs on the master track, while having open the Instr. Envelopes or the Sample editor. Soon as I switched from the Pattern Editor view, the cursor jumped to the track left of the master track. 
Is there a point in this or is it a bug or am I missing something?
Maybe because you can’t have instruments in the master track?
The cusor jumps to the next non master or send track, so that you can play notes via the keyboard. Would be strange if you are in the instrumenteditor and could not play the instrument via the keyboard, right?
it’s really incredible how much things you have to consider while writing an application like renoise. (and it’s even not the most complex one…)
i put off my hat.
Now that is an explanation that makes sense! 