Short description of error
Blender will instantly crash when the Ctrl key is pressed when placing a recently duplicated sequence in the Video Sequence Editor/VSE.
Seems to happen with all sequence types.
Exact steps for others to reproduce the error
switch to Video Editing layout,
load a sequence of some type into the VSE (or add an effect strip),
with the new sequence selected, press shift-d to duplicate it,
while still in the 'place sequence' mode, press ctrl to activate snapping.