consider adding option to *not* replace Emoji

[igalic]

Description

Most operating systems these days contain a complete and pre-installed (colour!) Emoji font that is specific to the system, or the user's configuration.

Steps to reproduce

• painstakingly install and configure a beautiful and perfect Emoji font and rejoice 😻
• use literally any web or electron app, including riot.im/app and see that it gets auto-replaced with something you don't want 😿

Version information

• Platform: web (in-browser) or desktop?

For the web app:

• Browser: Electron: 3.0.0-beta.5 / Chromium: 66.0.3359.181
• OS: Ubuntu
• URL: riot.im/app (i have not tried riot.im/develop yet)

[turt2live]

Good news! We're taking out emojione (the lib we use for this). Closing this to track it here: #9281