The bug has successfully landed and is aimed to be released in Firefox milestone 58. The process of fixing this bug can be found in my previous blog. Overall I believe this is a "good-first-bug" to work on because it gives you the fundamentals of using the MozillaBuild start-shell commands and the basic of Mercurial.
I have mentioned before that I have encountered some errors along the way, such as replacing the order of the name elements in the moz.build file and some file names has not been renamed, but, this was an easy fix. Besides those, there weren't any major issues.
The community in the forum of Bugzilla@Mozilla are genuine and respectful. I have been given the correct instructions and documentations on how to fix this bug by the reporter Mr. Brosset who has assigned the bug to me.
I have also noticed that some of my class mates have been working on a similar bug. I have offered my help on the Slack channel. As of now it seems they also finished and submitted a patch file.