IE11 p, h2, h3, undo, redo buttons not working in hallo RichText editor

[ababic]

Issue Summary

A few of the buttons on the hallo editor toolbar are failing to work in IE11. They don't throw errors, but they just don't seem to do anything.

The buttons we are seeing issues with are as follows, but there could be more that are effected:

• p
• h2
• h3
• undo
• redo

Steps to Reproduce

1. Running an up-to-date version of the wagtaildemo project with latest versions of wagtail/other dependencies installed
2. Create a new page that has a default RichText widget on the edit form somewhere (either as a RichTextField or a StreamField)
3. Try out the above buttons in IE11

[ralphjacobs]

> Quite a search but i think i found it.
> It has to do with the document.execCommand of contentEditable in IE.
> 
> IE needs a real 'tag':
>         document.execCommand('formatBlock', false, 'h1'); (doesn't work) vs
>         document.execCommand('formatBlock', false, '<h1>'); (works)
> 

[ralphjacobs]

http://jsfiddle.net/Xotic750/ZxePd/ (undo / redo) seems to work in IE11

[ralphjacobs]

Since there is a Deprecate Hallo.js issue: #2409
I'm really wondering if we should put time/effort on fixing this in Hallojs

[gasman]

Replacing hallo.js is probably (very roughly) about 6 months away, so if there's a simple fix for IE11 we can make in the meantime then we should go ahead and apply that. If not, then this ticket should be left open, and closed when hallo.js is finally killed off...

[thibaudcolas]

The new editor doesn't have this issue (it has other IE11 issues of its own though!). Hallo still affected, but closing anyway.