I originally saw this with a token action, but for simplification, if you type text @{target|Target|token_id}: @{selected|token_id} directly in the chat window, and don't have a token selected, you will get the message once You attempted to use a roll command looking for the value of a selected token, but no tokens are selected. It will also ask you to click on a target token. If you do, it will repeat the message above hundreds or thousands of times per second until you click the close dialog button on the select a target dialog box. It has obviously got some sort of infinite loop.
