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Running snaps are snaps that are constantly active, as opposed to one-time snaps invoked by SEKEs and the local menu. You can turn on running snaps by:
Selecting items from the Snaps menu.
Clicking the icon or combination of icons on the Snap Modes toolbar.
Using the *DrawO button next to the Coordinate Fields, and check the desired snaps.
Use hotkeys. You can view these in the Snaps menu. For example, Shift+V turns on Vertex snap.
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