[Evolution] WebKit editor undo problems

[Pete Biggs <pete biggs org uk>]

 Evo 3.16.2.1 on Fedora 22

I'm seeing some strange things with the webkit editor and I can't find
any references to the problem - probably looking in the wrong place.

The primary problem is that the undo when editing quoted replies is
seriously borked. For instance, and apologies if this gets difficult to
follow, take the text I sent myself - the words are numbered so you can
see what happens:

========
Lorem1 ipsum2 dolor3 sit4 amet5, vix6 ut7 congue8 inermis9, no0 quot1
porro2 accommodare3 mel4. Sea5 id6 nihil7 intellegat8 dissentiunt9,
accumsan0 pertinacia1 consequuntur2 ad3 vim4. Viderer5 evertitur6
referrentur7 vel9 id9, ei0 unum1 nulla2 voluptua3 cum4.
========

on replying I get:

============
On Thu, 2015-06-11 at 17:39 +0100, Pete Biggs wrote:
> Lorem1 ipsum2 dolor3 sit4 amet5, vix6 ut7 congue8 inermis9, no0 quot1
> porro2 accommodare3 mel4. Sea5 id6 nihil7 intellegat8 dissentiunt9,
> accumsan0 pertinacia1 consequuntur2 ad3 vim4. Viderer5 evertitur6
> referrentur7 vel9 id9, ei0 unum1 nulla2 voluptua3 cum4.
============

I delete the bottom line (by highlighting and <del>):

============
On Thu, 2015-06-11 at 17:39 +0100, Pete Biggs wrote:
> Lorem1 ipsum2 dolor3 sit4 amet5, vix6 ut7 congue8 inermis9, no0 quot1
> porro2 accommodare3 mel4. Sea5 id6 nihil7 intellegat8 dissentiunt9,
> accumsan0 pertinacia1 consequuntur2 ad3 vim4. Viderer5 evertitur6
============

I undo using Ctrl-Z

=========
On Thu, 2015-06-11 at 17:39 +0100, Pete Biggs wrote:
> Lorem1 ipsum2 dolor3 sit4 amet5, vix6 ut7 congue8 inermis9, no0 quot1
> porro2 accommodare3 mel4. Sea5 id6 nihil7 intellegat8 dissentiunt9,
> referrentur7 vel9 id9, ei0 unum1 nulla2 voluptua3 cum4.accumsan0
pertinacia1 consequuntur2 ad3 vim4. Viderer5 evertitur6
=========

So the undone delete is not placed back in its original position. 

Is this reproducible by others?

It's fairly annoying when trying to trim other people's posts and you
get it wrong and then can't undo the delete.

It also seems to behave much better in HTML mode. (And I'm damned if
I'm going to start composing all my emails in HTML.)

P.