Firefox update changes settings without warnings. Diff?

I would appreciate very much if Firefox update informed me about changes it does to my settings in detail. I want to have the chance to not be surprised by a new default search engine or a disabled https feature for example. I would very much appreciate to have the possibility to reconstruct my former settings by a comparison of backupped and current settings. This program behaviour becomes worse over the years, and I very much dislike it.

As long as it takes the FF developers to learn this simple rule I would very much appreciate to find out about all places where settings are stored so that I can script a historizing backup. I know places.sqlite and prefs.js of course and that these are the most important. My next step will be to search the Firefox documentation for information about exactly all settings. But I think there is more than the end user documentation tells me, and if some informed guy has already researched on this and knows something more, please share. I hope it will be in ascii files like prefs.js or at least readable by external programs like in places.sqlite so that I can program a diff. A snapshot program like e.g. RegShot will be fine to find registry changes and it snapshots the filesystem as well and compare »before« and »after snapshots« for me, but it will take some time to tell which is binary executable and which is readable configuration ... I hope there is no binary configuration file.

I already backup the whole profile directory but I need to know what Firefox has changed because I know that often there are good reasons to change a setting, and just restoring a whole configuration set will not work or will be contraproductive for some of the settings.

Please share your strategies with me. What is your solution for this?

[...]

It's worse than that. AFAICT, the settings are changed as part of a
silent update, which Mozilla is serving in an attempt to ensure better
security.

Unfortunately, every so often, that breaks something else. I had to
Restore the Surface 2 tablet because the wireless adapter was somehow
messed up. No wi-fi, no Bluetooth, troubleshoot couldn't fix it. I'm
pretty sure it was one of these silent updates, but I don't know how to
tell.

Have a good day,

--
Best,
Wolf K.
kirkwood40.blogspot.ca

That has been happening for quite a while. I first noticed it when it
first introduced the "do not track me" setting. I enabled that and the
next time I checked, it was disabled. That happened repeatedly without
my having to install a new version. My solution was to put the setting
into my user.js file. After that, the settings I wanted to keep stayed
put. The solution is to make a user.js file and copy into that any
setting you want to keep.

This page gives instructions on how to make a user.js file:
http://kb.mozillazine.org/User.js_file

Read the release notes prior to updating to a new version.
https://www.mozilla.org/en-US/firefox/releases/