What is up with the hex gibberish when linking items?

[Bandit.p99]

I have seen this happen a few times, it also may be when people are changing either auctions in the chat menu bar, you shift arrow backwards to delete an item/change post and hit enter right after, you need to arrow all the way to the end of your post again or this might happen ( if you have arrowed over a linked item ) If that makes sense lol sorry it early still.