I have noticed a bug where the quantity of a shard is reset to 1. It seems to happen when using the affix filter and the recovered shard(s) are excluded by the filter.
Through testing I can now reproduce the bug.
- Find/buy an item with a single affix for which you have N shards (N>=1) of that affix in the crafting window.
- Type anything in the filter which excludes the shard from the list.
- Shatter the item, recovering the shard.
- The shard will be added to the top of the list with a quantity of 1 (expected N+1).
A workaround it to always clear the filter before shattering an item.