Firefox notes, running Quantum and pre-Quantum

[darkoshi]

Firefox Developer Edition
The Firefox Developer Edition has its own profile path, so it can run side-by-side with a normal or ESR Firefox installation.

Firefox Portable
It has its own profile path, so it doesn't interfere with a normal Firefox installation. Regarding updates, it says "To upgrade to a newer version of Firefox Portable, just install a new copy of Firefox Portable right over your old one. All your data will be preserved. You can use the built in updater as well, but some non-personal files or directories may be left behind."

There are separate portable installs available, depending on which Firefox version you want to run:
https://portableapps.com/support/firefox_portable
https://portableapps.com/apps/internet/firefox-portable-esr
https://portableapps.com/apps/internet/firefox-developer-portable
https://portableapps.com/apps/internet/firefox-portable-nightly
https://portableapps.com/apps/internet/firefox_portable/test (beta)

Each one has its own profile folder. You can install and run multiple portable versions.

If you want to run multiple versions at the same time (or if you want to run the portable and regular versions at the same time), you should copy the FirefoxPortable.ini file from the portable version's "Other\Source" subfolder to its root folder, and edit it to update "AllowMultipleInstances" to true.

There is a separate app which lets you set up multiple profiles with Firefox Portable. But this only works with the regular portable version, not the ESR or other versions. There are other ways setting up multiple profiles which may work with the other versions.

This page has older versions of the regular Portable Firefox and ESR versions.

Firefox Versions
If you don't want to use the latest Firefox version, it is safer to run the ESR version than version 56, as the ESR version will continue to get security updates. The ESR channel won't get the v57 (Quantum) changes until around March 2018. Hopefully by then, more add-ons will have been updated to work with Quantum, or replacements will be available.

You can copy your profile (which has all your add-ons and settings) from a regular Firefox install to one of the portable versions.
However, profiles from Firefox 55 and later won't work with older Firefox versions. If you are downgrading from version 56 or 57 to the ESR version (which is currently at 52.5), you'll have to recreate your profile from scratch.

NoScript
The NoScript add-on is now available for Firefox 57, at least in a preliminary state. The interface is different than before. Either I haven't figured it out yet, or not everything is working quite right yet. I haven't found any good instructions for it yet.
(I tried setting "Temporarily Allow" for a few domains, but the webpage still didn't work, even though the same page did work with those same settings in Firefox 56.
Also, in Firefox 57, the domains shown in the NoScript drop-down don't include all of the domains that are listed in Firefox 56, for the same page.)

Status (etc) bar add-ons
Design and implement an API for Toolbars - bugzilla entry. Hopefully this will be implemented, so status bar add-ons can be made to work again.

Comments

[marahmarie]

Actually, I was thinking about Legacy: https://wiki.mozilla.org/Add-ons/Firefox57#Compatibility

According to the table at the link, "legacy extension[s] (bootstrapped, overlay, XUL etc)" that are "signed by AMO" and "unsigned" can be run in "Nightly, Developer Edition, unbranded beta, unbranded release"; if "signed by AMO" or "unsigned" then "YES with pref", if signed by Mozilla internally then simply "YES".

I posted about it on Nov. 9th after the topic was brought up by cellio in this post.

Unless I'm reading the table entirely wrong (which I can't and don't entirely rule out!).

[darkoshi]

That's interesting. I read it the same way you do. It's my guess that the info is simply wrong, but it's odd that the page has been updated lately, and that part wasn't changed.

If that were true, it would imply that nothing in the Firefox code base was changed which inherently prevents legacy addons from working. And that it's just an on/off switch somewhere to disallow it. I had thought that the Quantum changes were simply incompatible with legacy addons.

But I haven't seen it mentioned anywhere else that legacy addons would still work anywhere but older versions of Firefox.

I have read that PaleMoon and WaterFox, both Firefox forks, support both WebExtensions and Legacy addons. So that's another option to try. But I had issues with both of them the last time I tried them (which was quite a while back).

[marahmarie]

If that were true, it would imply that nothing in the Firefox code base was changed which inherently prevents legacy addons from working. And that it's just an on/off switch somewhere to disallow it. I had thought that the Quantum changes were simply incompatible with legacy addons.

Yeah, I can't figure it out - I took that page at it's word from Nov. 9th on, which was the only reason I was so puzzled at Legacy not working in Nightly. There are two possible flags you can set and I set them both and still could not get any Legacy add-on to work. So jumping down that rabbit hole has been a complete waste of time, and if that's because that page was or simply currently is wrong, someone should have updated it to reflect that at some point before Quantum rolled out.

I have read that PaleMoon and WaterFox, both Firefox forks, support both WebExtensions and Legacy addons.

I've used both pretty extensively in the distant-ish past, no problems outside of Firefox's usual ones (slow/buggy/crashes) but never could stick with them because a) I have trouble trusting a fork maintained by just one person not on the Mozilla project and b) lack of security updates - at least one if not both devs code only in their spare time; updates seem to seriously lag as a result.