There could be a scenario where you may need to let someone view the Heatmaps without logging in to Matomo, in this instance you can share a link of Heatmaps report.
Please follow the steps below:
1. Login to Matomo as Super User
2. Create a new user with View permission
3. Log out of Matomo
4. Login again as the newly created user
5. Create a new token_auth
6. Copy the token_auth created and save it
7. Click on Dashboard and Heatmaps > Manage Heatmaps
8. Click on the View (eyeball icon) and you will be redirected to a new tab
9. Append &token_auth=paste_created_token_here at the end of the URL
Note: As the token will be publicly visible make sure you only create a View only permission user, also note whoever can see the Heatmap report would be able to also access all of the Matomo data for this website. It is also possible to embed this report in an iFrame in a different website.