UndoManager support in Firefox

Question

I'm a little confused about how to use undoManager in Firefox. According to Mozilla, Firefox 20 now has support for it, but I can't figure out where. I've checked under document, Objects, etc., but can't find it anywhere. I'm sure I'm missing something obvious, so can anyone help?

Skirting

Answer 1

You have to set the "dom.undo_manager.enabled" preference to use it, so far, since the spec is still in flux.

Pavis

Thank you very much! But I had to add the preference manually, so I'm wondering why it wasn't just included and set to disabled by default. Anyway, I'll have to look into this feature more because I also thought undoManager would access the current undo stack, which it doesn't seem to be doing... – Skirting

Does it actually work? I made a simple document with an input, textarea and contenteditable div, and each always has a null undoManager property and document.undoManager.length is always 0. – Redroot

document.undoManager should work at least for some things, since there are automated tests that it does... See mxr.mozilla.org/mozilla-central/source/content/html/content/… – Pavis