The message shown to one friend can become a story told by many strangers.

Anything you write to one person exists in a form that travels. A screenshot takes a second, context does not travel with it, and a sentence written for someone who knows you can read very differently to people who do not. Most of the time nothing happens; occasionally a private line becomes a public artifact you cannot recall or explain.

Before sending something sharp about a third person, consider whether you would stand behind it out of context. Say the delicate thing out loud instead of in text. Keep the written record for things you would not mind being read twice.