Short description of error
F2 addon does not create faces unless you exit edit mode.
Exact steps for others to reproduce the error
Please look at the attached video as describing the steps is kind of cumbersome, the video screen cap is better at explaining the problem.
The error appeared as I was trying to fill a row of empty edges to quads, but nothings happened, then if I exited edit mode, upon re entry to edit mode, a new face was created were it was supposed to be the firs time around I was in edit model, as if F2 needed me to exit and re enter edit mode to create the face.
I reverted to factory settings and did the same test and it's also not working, so its not my local configuration of addons whats causing the problem.
Also when trying to create a face from a vertex I get this error in edit mode, however if I exit edit mode right afterwards, back in object mode the quad is created.
Traceback (most recent call last): File "C:\Program Files\Blender Foundation\blender-2.79-980a864-win64\blender-2.79.0-git.980a864-windows64\2.79\scripts\addons\mesh_f2.py", line 359, in invoke quad_from_vertex(bm, sel, context, event) File "C:\Program Files\Blender Foundation\blender-2.79-980a864-win64\blender-2.79.0-git.980a864-windows64\2.79\scripts\addons\mesh_f2.py", line 270, in quad_from_vertex face.smooth = smooth SystemError: error return without exception set location: <unknown location>:-1