Script opened from Editor, opens both in VS2015 and Monodevelop.

2. How we can reproduce it using the example you attached
This may be a precondition:
1. Have VS2015 and VSTU installed.
2. Install Unity and set Monodevelop as editor.
3. Run DA with latest trunk ini.

Steps to repro:
1. Install Unity + VSTU.
2. Run Unity. Create a new project or open existing. Create a new script/edit old.
3. VS starts to (slowly) open, and MD opens.

Actual result: Both VS2015 and MD editor open the same script.
Expected result: Only VS2015 is opened.