Previously sync-select in edge-select mode behaved in much the same
way as vertex selection, since a selected edge could cause a vertex
on an a disconnected UV island to be selected.
Now single vertices are no longer considered selected when the
Sticky-Mode is set to "Location" (the default).
Notes on changes when sync-select is enabled:
- The main change from a user perspective is edge & face select modes
show the selected edges.
- This resolves a problem in edge & face selection modes where it wasn't
possible to differentiate between a selected edge and two selected
vertices on either side of an unselected edge.
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