How do I make an extension for myself?

Add-ons Development
#1

Hello. Good time. I have edited the following extension and used my own colors. But I can use new extension just temporarily. With the help of about:debugging. What should I do?

https://github.com/WaldiPL/purplePrivateWindows

https://addons.mozilla.org/firefox/addon/purple-private-windows

#2

To be able to permanently install it, you need to sign the extension with addons.mozilla.org. See https://extensionworkshop.com/documentation/publish/ for guidance.