They probably don't but still kind of hard to be sure. In principle they could introduce it at any given time without anyone noticing for a while. Of course, on

They probably don't but still kind of hard to be sure. In principle they could introduce it at any given time without anyone noticing for a while. Of course, once someone does notice, the shit will hit the fan. Anyway, I share your nagging doubt and I'd never paste any text containing sensitive information into any text pane on a web page, not regexr, not JSON formatters, not anywhere.