Idea of Forward Message Icon
There is a rectangular envelope with the folded back. Underneath of it is an arrow pointing right as if to forward.
This Forward Message icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 6,100 icons, all in the same style and quality.