Microsoft Edge Group Policies for lists like Pop-ups do NOT combine -they replace unlike IE?

Here is the structure.
All Health authorities = OU = Tier 1
Group Policy linked to OU = "User and IE Edge Settings All"
User Configuration - Admin templates
Microsoft Edge (latest ADMX) = Pop up blocker = Allow = *.domain1.com *.domain2.com *.domain3.com
IE Settings = Pop up blocker = Allow = *.domain1.com *.domain2.com *.domain3.com

Child OU = Health Authority A (so this OU is inside the above one) = Tier 2
"Health Authority A User and IE Edge Settings All"
User Configuration
Microsoft Edge (latest ADMX) = Pop up blocker = Allow = *.siteextra1.com *.siteextra2.com *.siteextra3.com
IE Settings = Pop up blocker = Allow = *.siteextra1.com *.siteextra2.com *.siteextra3.com

Group Policies with Lists are SUPPOSED to be "cumulative" so if you add a Trusted site or a popup for IE in the Parent OU and different ones in the child OU they "merge" together.

End result for computer inside Child OU.
IE Settings = Pop up blocker = Allow = *.domain1.com *.domain2.com *.domain3.com *.siteextra1.com *.siteextra2.com *.siteextra3.com
Microsoft Edge = Pop up blocker = Allow = *.siteextra1.com *.siteextra2.com *.siteextra3.com

So instead of Edge "appending" the registry key like IE does, the policy deletes the Tier 1 settings and applies only the Tier 2 settings.

Note we have thousands of group policies with lists like Applocker, IE settings, Office settings in multiple policies. Lists in ALL those policies are always combined for the end result.

Edge Policies are the only one where a list is blown away entirely and not appended to if another policy adds to the list.

Note that Computer settings for IE always overwrite the same User settings. That is 100% expected.

However, if we set computer settings for Edge with lists in multiple policies the lists are not merged regardless if it is extensions, or anything else.