Envelope shelf edit tool does not work with selection made by clicking between markers

[petemus]

If you select a time region by clicking between markers in the ruler, you can't use the envelope shelf tool (or whatever it's called) to create an adjustable section for the envelope:

Should this work, or should you always select a region on the track itself? Making the selection with the ruler click would be an easy way to create a precise envelope section for marked sections.

If you first make a selection from the ruler and then select the envelope track, the shelf tool works correctly.