Having the exact same issue on some of our Macs. The only way I've found to get it to display the Categories is to scroll down and click on Notifications, then scroll back up to Browse click it to expand and it will display them again.
+1. have tried sudo jamf manage
and removing and reinstalling Self Service but no dice. Where is our Jamf QA?
Yes, definitely having the same issue on our fleet, though we can't get Categories to show back up at all.
On newly enrolled systems, we never get the "Categories"
Having the same problem with Categories not displaying in our 10.27.0 Dev Cloud environment but not in the Production Cloud environment so far. It seems to randomly affect some computers. I have tried a number of things on one of the affected machines but nothing has worked so far.
Same issue here...affecting devices at random
We're having the same issue - although luckily I've only seen it on 1 computer so far. I'm expecting more to surface at any point.
I did find that scrolling to notifications, then back to browse seems to work on my one afflicted computer, but it's only a temporary fix.
And then this happened.

Scrolling did not help us
I have the same behaviour here despite removing user caches, preferences and application support directories for Self Service so I've got an incident ticket in with Jamf.
Seeing the same at our office as well, but it is indeed sporadic.
We are having the same issue. Scrolling did not help. No items that were scoped show in the box. Only shows "History" and "Notifications." Multiple Macs on multiple OSes.
I noticed this on one of my test machines this morning. (It was a 2014 Mac mini that was running Catalina.) Scrolling and selecting Notifications and then Browse worked. However, if you collapse and re-expand Browse, the categories disappear again. If you don't see Browse at all, I noticed that reloading Self Service, selecting Notifications, and selecting the space where Browse is supposed to be displayed the notifications. This is a temporary solution as well.
We migrated from on-prem to the cloud on Friday, right before the update. Now all of our Macs are communicating with the old server rather than the cloud server. So any Macs that did update to 10.26 or 10.27 reverted back to 10.25.1 (which is what our on-prem was running). It's a good thing we didn't take the server down.
Scrolling has never seemed to help in my case. In my fleet of around 600 systems it either works or it doesn't. There's a wide variety of systems out there. On my sample of the 10 systems that I tested in my fleet:
• 1 is a M1 Mac
• 5 of the systems are macOS Mojave 10.14.6. One of these worked.
• 2 of the systems are running macOS Catalina 10.15.7. Both of these did not work.
• 3 systems (including the M1 Mac) are running macOS Big Sur. Two of these three work - with one running Big Sur 11.3 beta 2.
I tried finding a pattern on Saturday when I first encountered this in testing, but just could not find one. While working with Jamf Support yesterday, they had me remove the Self Service app and then I ran "sudo jamf policy" to re-install Self Service. I experienced the same problem again.
Here's an animated screenshot of what I'm seeing on affected systems:

Jamf no longer considers QA a priority, just getting things shipped...
The "new" Self Service is borked and I'm pretty sure they never tested it in the real world.
Well, they do have a beta program where we can do their testing for them... ;-)
Yeah, this is too widespread to be that much of a fluke. Wonder how on earth this made it through QA.
I heard back from Jamf Support. They are unable to reproduce the issue. The Jamf Support person has filed an internal product issue for this Self Service behavior. It is PI-009394. If you haven't already filed a Support Ticket, please file one. If you've filed one, you might want to add the PI-009394 that was created today for reference. I honestly don't know how many of my ~600 computers are affected, but it does cause confusion for our customers.
Also, it looks like someone filed a feature request here to revert back to the old Self Service app.
Yeah just got the PI confirmation as well.
We're seeing the same issue with varying macOS versions, so far no commonalities. I'm not sure how widespread it is yet. I've supplied requested logs to the ticket I opened earlier. We are waiting for Jamf Support to respond.
Thanks @john-hsu Just opened a ticket as well and referenced the PI.
I am seeing same issue, opened a ticket and referenced PI-009394. Pretty disappointed...
I rushed 10.27 into production to fix the MDM engine issues introduced in 10.26... Now this SS PI has derailed our internal Big Sur pilot. Not cool jamf. I need your product to work, work well at scale, and work reliably at scale. UI is very low on the reasons of why I advocate for jamf as a product. Please step up your QA game!
@Sonic84 I have been arguing these same points with Jamf support, and our rep, for some time now. Really getting frustrated with how unreliable things are becoming with Jamf.
Another problem that we are seeing is the icon badging only works when the Self Service app is open. Therefore, users are unaware that they have patch management updates available to install.
@jmuchow I have been seeing the same thing for a while now as well. Not really useful as a lot of users don't open Self Service unless they are either told they need to or they want to look for something.