You may find with the newer updates of Blender 2.8 beta, the Remove Doubles is no longer available in their panel. Can’t find a fix to this problem? Don’t worry here is a simple solution to resolve that double issue. Follow these basic guide to have your mesh clean.
1. Select your object and go into edit mode by pressing tab.
2. Select your vertices or edges which has overlapping doubles by pressing 1 or 2.
3. Go to Mesh > Clean up > Merge By Distance. (Currently there is no shortcut keys for this)
4. Check Unselected on. If the overlapping distance of the vertices [...]