It seemed that the problem seemed to happen by a different cause than Attachment 9126005 [details]. Attachment 9126005 [details] address the problem when tiles are dropped. But the remaining problem happened without tile drop situation.
Bug 1595014 Comment 13 Edit History
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It seemed that the problem seemed to happen by a different cause than Attachment 9126005 [details].
It seemed that the problem seemed to happen by a different cause than Attachment 9126005 [details]. Attachment 9126005 [details] addressed a problem during dropping tiles.