What
An attachment is an extra piece of information added to the conversation alongside messages. A new attachment type, advisor_stripped, is added once per request when the strip mode is strip_and_mark. The mode depends on the current state rather than on a setting, and relayThinkingStripOwed picks strip_and_mark for the main conversation. The attachment is on the list of hidden attachments and displays nothing.
Why
You will not see this marker on screen. It leaves a note in the conversation record that relayed thinking was removed.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The finding does not say what relayed thinking is or where it comes from.