I have found the commit that fixed the memory leak and applied it to emacs-24.3 and confirmed the memory leak is fixed. Hooray!

> Commit:57ae6509a3b6a274f89b9caea0284c6156470625[57ae650]
> Parents: a16cc46314
> Author: Jan Djärv <jan.h.d@swipnet.se>
> Date: 4 November 2013 17:57:17 GMT
> 
> Fix memory leaks in NS version.

Regarding the mumamo issues, I will try to contact the people maintaining that package, which as far as I know, is outside of emacs. That is why I figured it would not be something that was necessarily fixed before the next release.

On 19 Jan 2014, at 03:09, Stefan Monnier <monnier@iro.umontreal.ca> wrote:

>> Unfortunately I discovered that emacs has changed a lot and in particular
>> I am unable to use nxhtml and mumamo packages to edit JavaScript
>> inside a django template anymore. One error after another. Clearly some LISP
>> apis have changed.
> 
> Please report these problems (both to us and to the mumamo maintainers),
> since we need to solve them before the next release.
> 
> 
>        Stefan