If we create a custom group for SVG icons, if an icon is removed from the WP media section, it will appear broken in the Bricks icon palette and we will have to manually remove it from the Color manager.
We’ve addressed this in Bricks 2.4-beta (beta release), now available for manual download from your Bricks account.
Please read the changelog entry before testing, and let us know if you experience any issues. Note: beta builds are not recommended for production sites.