Slack Canvases at U-M

Environment

U-M Slack

Issue

What is a Slack canvas, and how can I use it?

Resolution

Slack canvases are a feature that provides an additional space ("canvas") for creating and sharing fully formatted content that won't fit into a single message, such as meeting notes or onboarding instructions. (They are similar to Google Docs but built-into Slack.)

Important things to note:

• You can add additional owners to your canvas. They will have the same permissions as the creator. This ensures that the canvas isn't abandoned/deleted when you leave the university and are no longer eligible for a U-M Slack account. (By default, external (non-UM) people who can view or edit a canvas cannot grant access to others. )
  1. Click Share at the top of your open canvas.
  2. Click People.
  3. Click the drop-down beside the individual you'd like to make an owner and select Owner.
• You can adjust the shared link settings to be accessible by Invite only, Viewable by anyone in University of Michigan, or Editable by anyone in University of Michigan. Use caution when opening the shared link to anyone in U-M Slack, as any individual can find it in their Canvases list under Files.
• Single-channel guests can only view or edit canvases that have been shared in channels they belong to.
• Canvases are no longer tied to channels or DMs. Instead, you can add a canvas tab at the top of your channel so it is easily accessible by channel members.
  • You can either click Add canvas or the plus (+) icon > Canvas at the top to add one to a channel or DM.
  • Channel/DM-specific canvases that existed before this change (pre-April 2025) were automatically assigned an owner based on who created them and can now be shared outside the channel/DM.
• You can limit who can share the canvas with additional people to just owners. This prevents collaborators from sharing the canvas with anybody in U-M Slack.
  1. Click Share at the top of your open canvas.
  2. Click Advanced Settings.
  3. Check the Only owners can share box.
• If you share a canvas link set to Only invited people in a public channel, it will be visible to everyone in that workspace. Avoid sharing canvas links in public channels if you don't want every workspace member to have access to it.
• Each canvas can be shared in up to 1000 channels. This does not apply to DMs.
  • The limit applies to both manual sharing and automated sharing through workflows.
  • You will receive an error message if you try to share a canvas after hitting the 1000-channel limit.
• There are some limitations to canvases in the Slack mobile app. It's not currently possible to:
  • Request edit access
  • Restore deleted canvases
• It isn't possible for Workspace Admins to manage all canvas sharing at the workspace level in U-M Slack. Because we are an Enterprise Grid environment, we do not have the same abilities as non-Grid workspaces.
• You can export canvases for use/retention outside of Slack. However, you have to "print" the canvas as a PDF to do so. (Both viewers and editors have this ability.)
  1. Click the three-dot icon in the top right of your open canvas.
  2. Select Print canvas.
  3. Select Adobe PDF​​​​​​​, Microsoft Print to PDF​​​​​​​,​​ or other available "print-to-PDF" option from the Printer drop-down menu.
     • This experience may differ between operating systems (Mac, Windows) and the apps you currently have installed on your desktop.

Refer to the Slack Help Center to learn more about creating/editing canvases and managing access permissions for canvases. Also, learn more about canvas accessibility (keyboard navigation and screen reader support).

Additional Information

Canvases were Slack's replacement for the Slack Posts feature (different than a Slack message), which retired in September 2023. All Slack Posts were converted to canvases. 

Need additional information or assistance? Contact the ITS Service Center.