<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta content="text/html;charset=UTF-8" http-equiv="Content-Type"></head><body ><div style='font-size:10pt;font-family:Verdana,Arial,Helvetica,sans-serif;'>> I'm not sure if OSM Messaging is built-in in JOSM, but it could be useful for quick messaging in this kind of case<br><br>No, due to missing API features. All that could be done is checking for unread messages.<br></div></body></html>