This happened yesterday when trying to figure out why the NavMeshBoundsVolume was crashing my editor so I started a New map to see if it was my current map causing the issue!

When I went and found a Material (wanted to use the cobblestone) I right clicked to drag it onto my surface and it lost the texture and went to default???? ... see below!

Several from that group did the same!?

Anybody experience this problem before???

... did I do a No No?
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