Try this. It doesn't work well tho and if u get it to work let us know if other can see what u linked cause that's the other issue.

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If you have a keyboard plugged in - enter text in the channel you want link the item in, hit B (O on ps4) to back out of the chat window and the text should still be there, then link an item. You'll have your text and the linked item in at the end. I haven't been able to figure it out with just a controller