The January 9, 2017 Canvas production update resulted in a name change for the Canvas icon font.
Content created with Cidi Labs' SaaS hosted version of the tools should show the new icons without issue. For any users who have content created using the older open source version of Design Tools (Kennethware) will need to update your legacy CSS code. You will need to find all instances of ‘canvas-icons’ and replace them with ‘InstructureIcons-Solid’.
Please let us know if you need more help with this.