diff --git a/bin/Packager/AppxManifest.xml b/bin/Packager/AppxManifest.xml
--- a/bin/Packager/AppxManifest.xml
+++ b/bin/Packager/AppxManifest.xml
@@ -1,11 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<Package xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10"
-         xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10"
-         xmlns:rescap="http://schemas.microsoft.com/appx/manifest/foundation/windows10/restrictedcapabilities"
-         xmlns:mp="http://schemas.microsoft.com/appx/2014/phone/manifest"
-         xmlns:com="http://schemas.microsoft.com/appx/manifest/com/windows10"
-         xmlns:desktop="http://schemas.microsoft.com/appx/manifest/desktop/windows10"
->
+<Package @{xml_namespaces}>
   <Identity Name="@{name}"
             Version="@{version}"
             Publisher="@{publisher}"
@@ -18,9 +12,7 @@
   <Dependencies>
     <TargetDeviceFamily  Name="Windows.Desktop" MinVersion="10.0.14316.0" MaxVersionTested="10.0.14316.0" />
   </Dependencies>
-  <Capabilities>
-    <rescap:Capability Name="runFullTrust" />
-  </Capabilities>
+  @{capabilities}
   <Resources>
     <Resource Language="en-us" />
 <!--    <Resource uap:Scale="100" />
diff --git a/bin/Packager/AppxPackager.py b/bin/Packager/AppxPackager.py
--- a/bin/Packager/AppxPackager.py
+++ b/bin/Packager/AppxPackager.py
@@ -33,6 +33,15 @@
 
 
 class AppxPackager(CollectionPackagerBase):
+    XMLNamespaces = r"""
+    xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10"
+         xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10"
+         xmlns:rescap="http://schemas.microsoft.com/appx/manifest/foundation/windows10/restrictedcapabilities"
+         xmlns:mp="http://schemas.microsoft.com/appx/2014/phone/manifest"
+         xmlns:com="http://schemas.microsoft.com/appx/manifest/com/windows10"
+         xmlns:desktop="http://schemas.microsoft.com/appx/manifest/desktop/windows10"
+         @{additional_xmlns}
+    """
     Extensions = r"""
         <uap:Extension Category="windows.fileTypeAssociation">
           <uap:FileTypeAssociation Name="@{craft_id}">
@@ -42,6 +51,11 @@
           </uap:FileTypeAssociation>
         </uap:Extension>"""
 
+    Capabilities = r"""
+        <rescap:Capability Name="runFullTrust" />
+        @{additional_capabilities}
+    """
+
     StartUp = r"""
         <desktop:Extension Category="windows.startupTask" Executable="@{startup_task}" EntryPoint="Windows.FullTrustApplication">
           <desktop:StartupTask TaskId="@{craft_id}" Enabled="true" DisplayName="@{display_name}" />
@@ -123,6 +137,18 @@
         if extensions:
             defines["extensions"] = f"<Extensions>{extensions}</Extensions>"
 
+        defines.setdefault("capabilities", AppxPackager.Capabilities)
+        capabilities = defines["capabilities"]
+
+        if capabilities:
+            defines["capabilities"] = f"<Capabilities>{capabilities}</Capabilities>"
+
+        defines.setdefault("xml_namespaces", AppxPackager.XMLNamespaces)
+        xml_namespaces = defines["xml_namespaces"]
+
+        if xml_namespaces:
+            defines["xml_namespaces"] = f"{xml_namespaces}"
+
         # compat with nsis
         if "shortcuts" in self.defines:
             defines.setdefault("executable", self.defines["shortcuts"][0]["target"])