Strange NS_ERROR_UNEXPECTED in CommandPatch.prototype.queryState

[valberg]

I wrote this to the maillist, but decided to make it into an actual issue since I've narrowed the problem a bit more down.

I'm using Firefox 30.0 on Mac OS X, and sometimes I get this strange error in the console: NS_ERROR_UNEXPECTED: and nothing more.

It says that it happens at line 3669 in scribe.js:

CommandPatch.prototype.queryState = function () {
  return document.queryCommandState(this.commandName);  // line 3669
};

I've figured out that the error can be "omitted" with the following:

CommandPatch.prototype.queryState = function () {
  if( this.commandName == 'insertUnorderedList' || this.commandName == 'insertOrderedList') {
      return false
  }
  return document.queryCommandState(this.commandName);
};

So somehow the list commands are forcing Firefox to throw an NS_ERROR_UNEXPECTED. Sometimes it's even NS_ERROR_FAILURE. But both cases have no more information associated.

Refrence to errors in Firefox: https://developer.mozilla.org/en-US/docs/Table_Of_Errors

[OliverJAsh]

I've seen this error happen in Firefox in two places, IIRC:

• When the contenteditable instance is a custom element (e.g. <foo>).
• When queryCommandState is called and there is a selection outside of a contenteditable instance.

Are either of these your issues?

If not, it would be good for you to provide steps for me to reproduce this bug on https://guardian.github.io/scribe.

[valberg]

Sadly it is neither of those cases. The contenteditable instance is a <div>, and it happens when I enter my editor page (so there is no selection).

I can't reproduce it on https://guardian.github.io/scribe - it probably has something to do with the rest of my application. But I have no idea how to debug it (other than the part where I just return false if the commandName is 'insertUnorderedList' or 'insertOrderedList'.

Any ideas?

[OliverJAsh]

Does Firefox provide you with a stack trace?

[valberg]

No, only NS_ERROR_UNEXPECTED: gets outputted in the console. Sorry for the lack of information. But I don't have anything more (what I know of).

[mgaerber]

I do get this error on https://guardian.github.io/scribe just by loading the page without any further action.
Reports error on line scribe.js (Zeile 3659)
return document.queryCommandState(this.commandName);

Firefox 30.0 on Win7

[hmgibson23]

Probably related to this I'm now seeing NS_ERROR_UNEXPECTED consistently on opening FF 30 on OS X

[hmgibson23]

This also seems related to this problem as the error always occurs in document.queryCommandState

https://bugzilla.mozilla.org/show_bug.cgi?id=562623

[danielberndt]

to further narrow down the root of the issue: the error only appears if the scribe-plugin-toolbar is used. (On FF31 / OS X 10.9.3)

[zbyte64]

I had this issue on FF35/Ubuntu 14.04 , I was using this with react and I think it was rewriting the toolbar elements. When I properly specified key attributes in react the error stopped as the elements were no longer being overwritten.

[zbyte64]

Never mind, still have the issue :(
At this point I am just checking if the error message is this and suppressing the error if it is.