Search notes:

Registry: HKEY_CLASSES_ROOT\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe/MicrosoftEdge/Main

Change home page

Apparently, the home page is not the same thing as the page that is shown when Edge is started.
In order to have a home page, the home button needs also be enabled(!).
The home page of Edge is hidden quite deep in the registry: 
@reg add "HKEY_CLASSES_ROOT\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe\MicrosoftEdge\Main" /v HomeButtonEnabled /t REG_DWORD /d            1  /f
@reg add "HKEY_CLASSES_ROOT\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe\MicrosoftEdge\Main" /v HomeButtonPage    /t REG_SZ    /d "about:blank" /f
Github repository about-Windows-Registry, path: /HKEY_CLASSES_ROOT/Local Settings/Software/Microsoft/Windows/CurrentVersion/AppContainer/Storage/microsoft.microsoftedge_8wekyb3d8bbwe/MicrosoftEdge/Main/home-page.bat
See also HKEY_CURRENT_USER\Software\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe\MicrosoftEdge\Protected – It is a violation of Windows Policy to modify. See aka.ms/browserpolicy.
See also ProtectedHompages in the key HKEY_CURRENT_USER\Software\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe\MicrosoftEdge\Protected – It is a violation of Windows Policy to modify. See aka.ms/browserpolicy

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