This reminds me of a suggestion I’ve had on my mibd for a while: if you customize a copy under Admin - > Customize - > Text Content and then the default copy gets changed via a discourse upgrade, you will never know about this. In some cases this doesn’t matter but in others it does, as in the example above. In some cases, such an upgrade might even break the rendering of the copy entirely because a variable has been added or taken away.
So how about some sort of notification or indicator for copies that have been updated? This may even be useful for copies that you have not customized, just as a “heads up, this has been changed, you might want to take a look”.
What exactly are the conditions that need to be met for the “this has been changed” notice to display, and where exactly will it be displayed? Simple mockup please
Whenever an upgrade results in a changed default copy (that way admins can check whether those changes are what they want or whether they need to customize)
Whenever an upgrade results in a changed default copy AND the site is currently not using the default copy (here the aim would merely be to alert admins to the existence of a new copy which they would never see because they are using a customized version)
Whenever an upgrade results in a default copy that is different to the default copy that was in place when the customized copy was first created AND the site is currently not using the default copy (this would ensure that the change notifications remain visible even across multiple upgrades, even when the latest upgrade did not result in any changes)
My preference is between 1 and 3. #1 because of it’s simplicity (as far as I can tell), and #3 because of its rigidity.
I didn’t include a mockup in the OP because I didn’t see it so much as a UI issue but simply a matter of being somehow informed, whatever is the simplest way to achieve this. But if you ask me for a visualization, here is one (which obviously combines several scenarios in one image):
