User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:50.0) Gecko/20100101 Firefox/50.0 Build ID: 20161208153507 Steps to reproduce: opened webpage with minified js and a source map with the console open. (when webpage is opened with console closed and console is later opened, everything works fine) Actual results: errors that come from the webpage point to the minified script line number Expected results: errors should be pointing to the source file line numbers.

I can reproduce this by opening a new tab, then opening the console, and then navigating. I can't reproduce it with other navigations. I suspect this is something we've seen before, where certain "built-in" pages aren't actually run in a content process, so the actors aren't installed early enough.

(In reply to Tom Tromey :tromey from comment #1) > I can reproduce this by opening a new tab, then opening the console, and then navigating. Ah yes, that's the exact steps I was doing when I ran into the bug. Didn't test navigating from other pages, just from the new tab.

This is fixed in my build, probably by bug 1366853. Could you try nightly and see if it is working for you? The other thing to be aware of is that if the script doing the log is GC'd, then it is possible not to see the source map. It depends on exactly when the GC happens.

I tried this using my examples repository and it works for me now. Please reopen or comment if this is in error.