fix visibility check

CURA-9424

plugins/3MFReader/WorkspaceDialog.qml

@@ -125,6 +125,7 @@ UM.Dialog
 
                     comboboxTitle: catalog.i18nc("@action:label", "Open With")
                     comboboxTooltipText: catalog.i18nc("@info:tooltip", "How should the conflict in the machine be resolved?")
+                    comboboxVisible: workspaceDialog.visible && manager.updatableMachinesModel.count > 1
                     combobox: Cura.ComboBox
                     {
                         id: machineResolveComboBox
@@ -261,6 +262,7 @@ UM.Dialog
 
                     comboboxTitle: catalog.i18nc("@action:label", "Open With")
                     comboboxTooltipText: catalog.i18nc("@info:tooltip", "How should the conflict in the profile be resolved?")
+                    comboboxVisible: manager.qualityChangesConflict
                     combobox: Cura.ComboBox
                     {
                         id: qualityChangesResolveComboBox
@@ -315,6 +317,7 @@ UM.Dialog
 
                     comboboxTitle: catalog.i18nc("@action:label", "Open With")
                     comboboxTooltipText: catalog.i18nc("@info:tooltip", "How should the conflict in the material be resolved?")
+                    comboboxVisible: manager.materialConflict
 
                     combobox: Cura.ComboBox
                     {

plugins/3MFReader/WorkspaceSection.qml

@@ -30,7 +30,7 @@ Item
         height: visible ? UM.Theme.getSize("default_margin").height : 0
         anchors.top: parent.top
         anchors.right: parent.right
-        visible: combobox.visible
+        visible: comboboxVisible
         text: comboboxTooltipText
 
         UM.Label
@@ -39,7 +39,7 @@ Item
             anchors.top: parent.top
             anchors.left: parent.left
             anchors.bottomMargin: UM.Theme.getSize("default_margin").height
-            visible: combobox.visible
+            visible: comboboxVisible
             text: ""
             font: UM.Theme.getFont("default_bold")
         }