Replies

For installation of the modified FRPFE extension, in Firefox,
the extension package must be submitted to Mozilla, where it
will be run thru their Add-on approval process, that includes,
some of the Add-on ingredients being signed.

That signing process creates the META-INF folder and the files
within that META-INF folder. (Refer to my reply 64.)

Among the 3 FRPFE extension file sources, there are 3 XPI files
with different names:

1) frpfe.xpi
2) frpfe@cynwoody.appspot.com.xpi
3) frpostfenhancer.xpi

I used the 2nd, expanded that, and then edited the "manifest.json"
file and the "script.js" file. I ignored the META-INF folder,
because it is a Mozilla production, and I was aiming to install
the extension in Brave Browser (Chromium engine).

The parent folder and package name for my revision of cynwoody's
work, that I produced as a Brave Browser extension, remained the
original: "frpfe@cynwoody.appspot.com" without the "xpi" filename
extension.

For Brave Browser, you load the folder, not the .xpi / .zip file.

In order to submit a package similar to what I built for use with
Brave Browser, but now for Firefox . . . and, requiring Mozilla
approval and signing - that is acceptable for Firefox installation,
I would need to create a new parent name for the package to be
submitted, probably:

FRPFEXT
     date.txt
     FRPFE.png
     manifest.json
     script.js

I would .zip compress that folder, change the resulting filename
extension to "xpi" and thus submit the extension as:

"FRPFEXT.xpi"

To: Mozilla's Submitting an add-on webpage. There, scroll down
to section "Self-distribution", and follow the steps.

You might do the same, for your own extension.

But at present, I want to know more about "What am I getting into?"
if/when Mozilla might require that I join their Mozilla Developer
Network. (I certainly am not a developer.)