Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Interfacer - Collection of more than 200+ free design resources
story.to.design - Keep your Figma components up to date with code
Facebook Design Resources - A collection of free resources made by designers at Facebook
Designmodo - Timesaving tools for designers, developers and marketers. Designmodo offers website and email builders.
Freebiesbug - Collection of the best free web design resources.