webextensions-examples/emoji-substitution

Emoji Substitution

What it does

Replaces words that describe an emoji with the emoji itself. This runs as a content script and scans web pages, looking for text that can be replaced with emoji. As an example, after installing visit https://mozilla.org and notice that the text "firefox" should change.

What it shows

A good example for beginners that can be used as a "make your first add-on" tutorial and / or referenced to create other add-ons.