To add a custom social media icon in the website footer of Odoo (v16–v18):

 Steps Using Website Builder (No Code)

1. Go to Website → Edit
2. Scroll to Footer, then click the existing social media icons block.
3. Click ➕ (Add Icon) → Select from available icons (Font Awesome icons are used).
4. Add your social link URL.
5. Save and publish.

Hello Teddy Ong,

I would like to inform you that you can easily add a new social media icon to the website footer using the website editor.

For detailed guidance, please refer to the video linked below:

https://drive.google.com/file/d/1Z8UPFzPLRaybO1QX3OFkpYF0jNHyItt_/view?usp=sharing

For more details, you can also refer to  the documentation: https://www.odoo.com/documentation/18.0/applications/websites/website/web_design/building_blocks/inner_content.html?highlight=social%20media%20icon

I hope you find this helpful. 

Thank you, and have a wonderful day!