Console.jsm uses `JSON.stringify` when printing error objects via `dump`. Unfortunately, this makes the error a bit vague: for example, https://treeherder.mozilla.org/logviewer.html#?job_id=19148268&repo=try#L4186. It would help if we could log the error name and message in this case. I think it's fine to omit the stack, since that could take up multiple lines and introduce noise.

Review commit: https://reviewboard.mozilla.org/r/45587/diff/#index_header See other reviews: https://reviewboard.mozilla.org/r/45587/

Comment on attachment 8740148 [details] MozReview Request: Bug 1263747 - Log error messages when stringifying errors. r?bgrins https://reviewboard.mozilla.org/r/45587/#review42133 nice ::: toolkit/modules/Console.jsm:117 (Diff revision 1) > + The object to check > + * @return {boolean} > + Is this object an error? > + */ > +function isError(aThing) { > + return (typeof aThing.name == "string" && Think it'd be safest to include `if (typeof aThing == "object")` in this chain so we don't have to assume it's already been null checked