Sometimes, pressing 1-9 in your inventory to swap items, placing one of the blocks you swapped will turn it into the other one... I was using Creative Mode here.
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MC-106994
Pressing 1-9 to swap items makes the blocks act weird...
Resolved
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0
migrated
(Unassigned)
Unconfirmed
Minecraft 1.10.2, Minecraft 16w35a, Minecraft 16w36a
Retrieved