Links included in the notification emails sent to users (e.g. links to collections/workflows in our Private Gallery) or copied from the browser address bar only works for public workflows or for workflows in your private studio.
If the workflow is in a collection shared with you, clicking on the link takes you to what seems to be the gallery page for the workflow asking you to sign in, but after you sign-in you are redirected to the gallery home page and not back to the workflow page.
The same occurs regardless if you're already signed-in or not.
This was related to support case: 00352021