If you CTRL+Pick Block a Conditional command block of any kind, it doesn't keep the Conditionality. This is a bug that I think has an easy fix since 1.13 is a technical bugfix update. The best way of fixing this is to make it so conditional command blocks and unconditional command blocks are 2 separate items/blocks instead of blockstates. This will allow players to easily identify conditional command blocks as well, and this will go for all 3 types of command blocks.