I'm using 2.8 Is there no default short key combo to remove duplicates now?
I see that I can quickly add a shortcut for it - but it seems to me that it's something that should be in the mesh (w) menu. I use it all the time.
As of writing this answer, the option is
not present in Blender, or at least not searchable through F3 and buried somewhere deep. What works instead, is merging by distance by either of these methods:
A panel with settings will appear on bottom left:
After clicking it, it will expand:
Beware, that this will remove not only vertices that have the exact same coordinates, but also those that are within 0.0001m of each-other. You can decrease this value to as low as 0.000001m.
Edit: thanks to the comments from Hikariztw and JtheNinja, I investigated the issue and indeed the old remove doubles worked exactly the same. In Blender 2.79 the merge distance seemed to default to zero:
but after clicking the input field it would reveal that the 0.000 was just a rounded view of an actual non-zero value:
In both cases (Blender 2.79 and Blender 2.8) the default value is 0.0001m and the minimum value is 0.000001m (in Blender 2.79 you have to go to scene settings and set metric system for length in order to see 1 micrometer instead of 0.000001 without a unit).
Blender 2.8 is in development. It's an unfinished alpha product constantly changing hour after hour. So if you're not prepared to constantly change with it, consider waiting for the 2.80 release.
BTW, it seems to be in the "Context menu" (W, previously called "Specials menu") in today's build. But you have to be in vertex selection, as it's an operation on vertices and the new context menu is meant to show different tools according to the context: