@richard_gardner ...
...because Canvas never sends out a list of new fixes) is unexplainable, except for Canvas' incompetence.
Do you know if you had submitted a ticket about this to Canvas Support? If you did, then you should have been added to any existing tickets they had about this issue...and then when and if things are fixed, you would have been notified that way. At least, that's the way I understand how the Canvas Help Desk staff operates currently.
Also (I'm not sure if this totally addresses your concern, but I am providing you the information just in case) ... I'm not sure if you frequent the Canvas Community website much, but Instrucure (the folks that make Canvas) distributes their Release Notes documents every month here for the public to review. You can always find their Release Notes posted at:
Canvas Releases - Instructure Community (canvaslms.com)
In addition, this document details their schedule for all their Release Notes:
What is the Canvas release schedule for beta, prod... - Instructure Community (canvaslms.com)
Finally, there is a good FAQs document to answer additional information about the Release Notes and the Deploy Notes you see listed on the first link I provided:
Release Notes Summary (FAQ) - Instructure Community (canvaslms.com)
When I was a Canvas administrator in higher education, I made sure to follow these updates and then post announcements to our Canvas Dashboard to let our faculty know ahead of time that new updates and/or features were coming to their Canvas courses...so that they could be prepared for any changes. I'm not sure if your school Canvas administrator has done anything similar, but this might be something that you might make as a suggestion to that person. (Maybe they already do this...which is great!) If you are using the FFT (Free For Teacher) version of Canvas, I can see where you might not see these kinds of monthly updates right away. That's where I would encourage you to follow these areas of the Community so that you stay updated. You can "Subscribe" to those areas of the Community so that you are notified when new things are posted.
I hope that I have helped to clarify things for you, Richard. And, I hope that you'll be able to take advantage of the Release Notes/Deploy Notes areas here in the Community to check out the new things that Instructure has been working on.
Take care...be well.