diff --git a/cura/CuraApplication.py b/cura/CuraApplication.py
index 9e016561d5..ab348ae471 100755
--- a/cura/CuraApplication.py
+++ b/cura/CuraApplication.py
@@ -220,7 +220,8 @@ class CuraApplication(QtApplication):
             "LocalFileOutputDevice",
             "TranslateTool",
             "FileLogger",
-            "XmlMaterialProfile"
+            "XmlMaterialProfile",
+            "PluginBrowser"
         ])
         self._physics = None
         self._volume = None
diff --git a/cura/Settings/CuraStackBuilder.py b/cura/Settings/CuraStackBuilder.py
index 7a48b1657e..09815da319 100644
--- a/cura/Settings/CuraStackBuilder.py
+++ b/cura/Settings/CuraStackBuilder.py
@@ -29,7 +29,8 @@ class CuraStackBuilder:
             return None
 
         machine_definition = definitions[0]
-        generated_name = registry.createUniqueName("machine", "", machine_definition.name, machine_definition.name)
+
+        generated_name = registry.createUniqueName("machine", "", name, machine_definition.name)
         # Make sure the new name does not collide with any definition or (quality) profile
         # createUniqueName() only looks at other stacks, but not at definitions or quality profiles
         # Note that we don't go for uniqueName() immediately because that function matches with ignore_case set to true
@@ -44,13 +45,7 @@ class CuraStackBuilder:
             variant = "default",
         )
 
-        # after creating a global stack can be set custom defined name
-        if name != generated_name:
-            name = registry.createUniqueName("machine", "", name, machine_definition.name)
-            if registry.findContainers(id = name):
-                name = registry.uniqueName(name)
-
-            new_global_stack.setName(name)
+        new_global_stack.setName(generated_name)
 
         for extruder_definition in registry.findDefinitionContainers(machine = machine_definition.id):
             position = extruder_definition.getMetaDataEntry("position", None)
diff --git a/plugins/3MFReader/ThreeMFWorkspaceReader.py b/plugins/3MFReader/ThreeMFWorkspaceReader.py
index 6de4ddc998..7e185c8d9f 100755
--- a/plugins/3MFReader/ThreeMFWorkspaceReader.py
+++ b/plugins/3MFReader/ThreeMFWorkspaceReader.py
@@ -222,10 +222,12 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
             elif container_type == "definition_changes":
                 definition_name = instance_container.getName()
                 num_settings_overriden_by_definition_changes += len(instance_container._instances)
+                # Check if definition changes already exists.
                 definition_changes = self._container_registry.findInstanceContainers(id = container_id)
-                containers_found_dict["definition_changes"] = True
                 # Check if there is any difference the loaded settings from the project file and the settings in Cura.
                 if definition_changes:
+                    containers_found_dict["definition_changes"] = True
+                    # Check if there really is a conflict by comparing the values
                     if definition_changes[0] != instance_container:
                         definition_changes_conflict = True
             elif container_type == "quality":
@@ -357,7 +359,7 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
         #  - new:       create a new container
         #  - override:  override the existing container
         #  - None:      There is no conflict, which means containers with the same IDs may or may not be there already.
-        #               If there is an existing container, there is no conflict between the them, and default to "override"
+        #               If there is an existing container, there is no conflict between them, and default to "override"
         #               If there is no existing container, default to "new"
         #
         # Default values
@@ -600,7 +602,9 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
                         if self._resolve_strategies["machine"] == "new":
                             # The machine is going to get a spiffy new name, so ensure that the id's of user settings match.
                             old_extruder_id = instance_container.getMetaDataEntry("extruder", None)
-                            if old_extruder_id:
+                            # Note that in case of a quality_changes extruder means the definition id of the extruder stack
+                            # For the user settings, it means the actual extruder stack id it's assigned to.
+                            if old_extruder_id and old_extruder_id in extruder_stack_id_map:
                                 new_extruder_id = extruder_stack_id_map[old_extruder_id]
                                 instance_container.setMetaDataEntry("extruder", new_extruder_id)
 
diff --git a/plugins/3MFReader/WorkspaceDialog.py b/plugins/3MFReader/WorkspaceDialog.py
index d80fc8b8b5..fc46a3daec 100644
--- a/plugins/3MFReader/WorkspaceDialog.py
+++ b/plugins/3MFReader/WorkspaceDialog.py
@@ -233,13 +233,15 @@ class WorkspaceDialog(QObject):
             self._result["quality_changes"] = None
         if "definition_changes" in self._result and not self._has_definition_changes_conflict:
             self._result["definition_changes"] = None
-
-        # If the machine needs to be re-created, the definition_changes should also be re-created.
-        if "machine" in self._result and self._result["machine"] == "new" and self._result["definition_changes"] is None:
-            self._result["definition_changes"] = "new"
-
         if "material" in self._result and not self._has_material_conflict:
             self._result["material"] = None
+
+        # If the machine needs to be re-created, the definition_changes should also be re-created.
+        # If the machine strategy is None, it means that there is no name conflict with existing ones. In this case
+        # new definitions changes are created
+        if "machine" in self._result and self._result["machine"] == "new" or self._result["machine"] is None and self._result["definition_changes"] is None:
+            self._result["definition_changes"] = "new"
+
         return self._result
 
     def _createViewFromQML(self):
diff --git a/plugins/PluginBrowser/PluginBrowser.py b/plugins/PluginBrowser/PluginBrowser.py
index 7a3b52b99f..0037d4bc59 100644
--- a/plugins/PluginBrowser/PluginBrowser.py
+++ b/plugins/PluginBrowser/PluginBrowser.py
@@ -23,9 +23,9 @@ i18n_catalog = i18nCatalog("cura")
 
 
 class PluginBrowser(QObject, Extension):
-    def __init__(self, parent = None):
+    def __init__(self, parent=None):
         super().__init__(parent)
-        self.addMenuItem(i18n_catalog.i18nc("@menuitem", "Browse plugins"), self.browsePlugins)
+
         self._api_version = 1
         self._api_url = "http://software.ultimaker.com/cura/v%s/" % self._api_version
 
@@ -92,6 +92,7 @@ class PluginBrowser(QObject, Extension):
     def isDownloading(self):
         return self._is_downloading
 
+    @pyqtSlot()
     def browsePlugins(self):
         self._createNetworkManager()
         self.requestPluginList()
diff --git a/plugins/UM3NetworkPrinting/NetworkPrinterOutputDevice.py b/plugins/UM3NetworkPrinting/NetworkPrinterOutputDevice.py
index 994f332d46..3ea48be33c 100755
--- a/plugins/UM3NetworkPrinting/NetworkPrinterOutputDevice.py
+++ b/plugins/UM3NetworkPrinting/NetworkPrinterOutputDevice.py
@@ -50,7 +50,8 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
         self._api_prefix = api_prefix
 
         self._gcode = None
-        self._print_finished = True  # _print_finsihed == False means we're halfway in a print
+        self._print_finished = True  # _print_finished == False means we're halfway in a print
+        self._write_finished = True  # _write_finished == False means we're currently sending a G-code file
 
         self._use_gzip = True  # Should we use g-zip compression before sending the data?
 
@@ -650,7 +651,16 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
     #   \param filter_by_machine Whether to filter MIME types by machine. This
     #   is ignored.
     #   \param kwargs Keyword arguments.
-    def requestWrite(self, nodes, file_name = None, filter_by_machine = False, file_handler = None, **kwargs):
+    def requestWrite(self, nodes, file_name=None, filter_by_machine=False, file_handler=None, **kwargs):
+
+        # Check if we're already writing
+        if not self._write_finished:
+            self._error_message = Message(
+                i18n_catalog.i18nc("@info:status",
+                                   "Sending new jobs (temporarily) blocked, still sending the previous print job."))
+            self._error_message.show()
+            return
+
         if self._printer_state not in ["idle", ""]:
             self._error_message = Message(
                 i18n_catalog.i18nc("@info:status", "Unable to start a new print job, printer is busy. Current printer status is %s.") % self._printer_state,
@@ -750,6 +760,9 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
                                                  )
             return
 
+        # Indicate we're starting a new write action, is set back to True in the startPrint() method
+        self._write_finished = False
+
         self.startPrint()
 
     def _configurationMismatchMessageCallback(self, button):
@@ -909,6 +922,7 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
             ##  Post request + data
             self._post_reply = self._manager.post(self._post_request, self._post_multi_part)
             self._post_reply.uploadProgress.connect(self._onUploadProgress)
+            self._post_reply.finished.connect(self._onUploadFinished)  # used to unblock new write actions
 
         except IOError:
             self._progress_message.hide()
@@ -1245,6 +1259,10 @@ class NetworkPrinterOutputDevice(PrinterOutputDevice):
             self._progress_message.setProgress(0)
             self._progress_message.hide()
 
+    ## Allow new write actions (uploads) again when uploading is finished.
+    def _onUploadFinished(self):
+        self._write_finished = True
+
     ##  Let the user decide if the hotends and/or material should be synced with the printer
     def materialHotendChangedMessage(self, callback):
         Application.getInstance().messageBox(i18n_catalog.i18nc("@window:title", "Sync with your printer"),
diff --git a/resources/qml/Actions.qml b/resources/qml/Actions.qml
index 68a3baa768..cc27520a02 100755
--- a/resources/qml/Actions.qml
+++ b/resources/qml/Actions.qml
@@ -61,6 +61,9 @@ Item
 
     property alias configureSettingVisibility: configureSettingVisibilityAction
 
+    property alias browsePlugins: browsePluginsAction
+    property alias configurePlugins: configurePluginsAction
+
     UM.I18nCatalog{id: catalog; name:"cura"}
 
     Action
@@ -362,4 +365,18 @@ Item
         text: catalog.i18nc("@action:menu", "Configure setting visibility...");
         iconName: "configure"
     }
+
+    Action
+    {
+        id: browsePluginsAction
+        text: catalog.i18nc("@action:menu", "Browse plugins...")
+        iconName: "plugins_browse"
+    }
+
+    Action
+    {
+        id: configurePluginsAction
+        text: catalog.i18nc("@action:menu", "Installed plugins...");
+        iconName: "plugins_configure"
+    }
 }
diff --git a/resources/qml/Cura.qml b/resources/qml/Cura.qml
index 9fecf23ca9..ca32a6eaab 100755
--- a/resources/qml/Cura.qml
+++ b/resources/qml/Cura.qml
@@ -207,7 +207,7 @@ UM.MainWindow
                         id: sub_menu
                         title: model.name;
                         visible: actions != null
-                        enabled:actions != null
+                        enabled: actions != null
                         Instantiator
                         {
                             model: actions
@@ -226,6 +226,15 @@ UM.MainWindow
                 }
             }
 
+            Menu
+            {
+                id: plugin_menu
+                title: catalog.i18nc("@title:menu menubar:toplevel", "P&lugins")
+
+                MenuItem { action: Cura.Actions.browsePlugins }
+                MenuItem { action: Cura.Actions.configurePlugins }
+            }
+
             Menu
             {
                 title: catalog.i18nc("@title:menu menubar:toplevel","P&references");
@@ -543,6 +552,30 @@ UM.MainWindow
         }
     }
 
+    // show the installed plugins page in the preferences dialog
+    Connections
+    {
+        target: Cura.Actions.configurePlugins
+        onTriggered:
+        {
+            preferences.visible = true
+            preferences.setPage(5)
+        }
+    }
+
+    UM.ExtensionModel {
+        id: curaExtensions
+    }
+
+    // show the plugin browser dialog
+    Connections
+    {
+        target: Cura.Actions.browsePlugins
+        onTriggered: {
+            curaExtensions.callExtensionMethod("Plugin Browser", "browsePlugins")
+        }
+    }
+
     Timer
     {
         id: createProfileTimer
diff --git a/resources/qml/SaveButton.qml b/resources/qml/SaveButton.qml
index b613b1217e..7423fc2368 100644
--- a/resources/qml/SaveButton.qml
+++ b/resources/qml/SaveButton.qml
@@ -43,7 +43,7 @@ Item {
         }
     }
 
-    Text {
+    Label {
         id: statusLabel
         width: parent.width - 2 * UM.Theme.getSize("sidebar_margin").width
         anchors.top: parent.top
diff --git a/resources/qml/Sidebar.qml b/resources/qml/Sidebar.qml
index 4fdeac752f..99948fc4fc 100755
--- a/resources/qml/Sidebar.qml
+++ b/resources/qml/Sidebar.qml
@@ -114,7 +114,7 @@ Rectangle
         }
     }
 
-    Text {
+    Label {
         id: settingsModeLabel
         text: !hideSettings ? catalog.i18nc("@label:listbox", "Print Setup") : catalog.i18nc("@label:listbox","Print Setup disabled\nG-code files cannot be modified");
         anchors.left: parent.left
diff --git a/resources/qml/SidebarHeader.qml b/resources/qml/SidebarHeader.qml
index d20feca8d6..9269984a2a 100644
--- a/resources/qml/SidebarHeader.qml
+++ b/resources/qml/SidebarHeader.qml
@@ -363,7 +363,7 @@ Column
                 visible: !Cura.MachineManager.isCurrentSetupSupported
             }
 
-            Text {
+            Label {
                 id: materialInfoLabel
                 wrapMode: Text.WordWrap
                 text: catalog.i18nc("@label", "<a href='%1'>Check material compatibility</a>")
diff --git a/resources/qml/SidebarSimple.qml b/resources/qml/SidebarSimple.qml
index f8c3173c11..03d3e2cd10 100644
--- a/resources/qml/SidebarSimple.qml
+++ b/resources/qml/SidebarSimple.qml
@@ -154,7 +154,7 @@ Item
                     }
                 }
 
-                Text
+                Label
                 {
                     id: qualityRowTitle
                     text: catalog.i18nc("@label", "Layer Height")
@@ -171,11 +171,11 @@ Item
                     {
                         model: qualityModel
 
-                        Text
+                        Label
                         {
                             anchors.verticalCenter: parent.verticalCenter
                             anchors.top: parent.top
-                            anchors.topMargin: UM.Theme.getSize("sidebar_margin").height / 2
+                            anchors.topMargin: parseInt(UM.Theme.getSize("sidebar_margin").height / 2)
                             color: (Cura.MachineManager.activeMachine != null && Cura.ProfilesModel.getItem(index).available) ? UM.Theme.getColor("quality_slider_available") : UM.Theme.getColor("quality_slider_unavailable")
                             text:
                             {
@@ -194,13 +194,13 @@ Item
                                 // Make sure the text aligns correctly with each tick
                                 if (qualityModel.totalTicks == 0) {
                                     // If there is only one tick, align it centrally
-                                    return ((base.width * 0.55) - width) / 2
+                                    return parseInt(((base.width * 0.55) - width) / 2)
                                 } else if (index == 0) {
                                     return (base.width * 0.55 / qualityModel.totalTicks) * index
                                 } else if (index == qualityModel.totalTicks) {
                                     return (base.width * 0.55 / qualityModel.totalTicks) * index - width
                                 } else {
-                                    return (base.width * 0.55 / qualityModel.totalTicks) * index - (width / 2)
+                                    return parseInt((base.width * 0.55 / qualityModel.totalTicks) * index - (width / 2))
                                 }
                             }
                         }
@@ -310,7 +310,7 @@ Item
                     }
                 }
 
-                Text
+                Label
                 {
                     id: speedLabel
                     anchors.top: speedSlider.bottom
@@ -322,7 +322,7 @@ Item
                     color: UM.Theme.getColor("text")
                 }
 
-                Text
+                Label
                 {
                     anchors.bottom: speedLabel.bottom
                     anchors.left: speedSlider.left
@@ -333,7 +333,7 @@ Item
                     horizontalAlignment: Text.AlignLeft
                 }
 
-                Text
+                Label
                 {
                     anchors.bottom: speedLabel.bottom
                     anchors.right: speedSlider.right
@@ -360,7 +360,7 @@ Item
 
                 width: UM.Theme.getSize("sidebar").width * .45 - UM.Theme.getSize("sidebar_margin").width
 
-                Text
+                Label
                 {
                     id: infillLabel
                     text: catalog.i18nc("@label", "Infill")
@@ -385,7 +385,7 @@ Item
                 anchors.top: infillCellLeft.top
                 anchors.topMargin: UM.Theme.getSize("sidebar_margin").height
 
-                Text {
+                Label {
                     id: selectedInfillRateText
 
                     //anchors.top: parent.top
@@ -482,7 +482,7 @@ Item
 
                     anchors.right: parent.right
                     anchors.top: parent.top
-                    anchors.topMargin: UM.Theme.getSize("sidebar_margin").height / 2
+                    anchors.topMargin: parseInt(UM.Theme.getSize("sidebar_margin").height / 2)
 
                     // we loop over all density icons and only show the one that has the current density and steps
                     Repeater
@@ -533,7 +533,7 @@ Item
                     property alias _hovered: enableGradualInfillMouseArea.containsMouse
 
                     anchors.top: infillSlider.bottom
-                    anchors.topMargin: UM.Theme.getSize("sidebar_margin").height / 2 // closer to slider since it belongs to the same category
+                    anchors.topMargin: parseInt(UM.Theme.getSize("sidebar_margin").height / 2) // closer to slider since it belongs to the same category
                     anchors.left: infillCellRight.left
 
                     style: UM.Theme.styles.checkbox
@@ -563,10 +563,10 @@ Item
                         }
                     }
 
-                    Text {
+                    Label {
                         id: gradualInfillLabel
                         anchors.left: enableGradualInfillCheckBox.right
-                        anchors.leftMargin: UM.Theme.getSize("sidebar_margin").width / 2
+                        anchors.leftMargin: parseInt(UM.Theme.getSize("sidebar_margin").width / 2)
                         text: catalog.i18nc("@label", "Enable gradual")
                         font: UM.Theme.getFont("default")
                         color: UM.Theme.getColor("text")
@@ -621,13 +621,13 @@ Item
             //
             //  Enable support
             //
-            Text
+            Label
             {
                 id: enableSupportLabel
                 visible: enableSupportCheckBox.visible
 
                 anchors.top: infillCellRight.bottom
-                anchors.topMargin: UM.Theme.getSize("sidebar_margin").height * 1.5
+                anchors.topMargin: parseInt(UM.Theme.getSize("sidebar_margin").height * 1.5)
                 anchors.left: parent.left
                 anchors.leftMargin: UM.Theme.getSize("sidebar_margin").width
                 anchors.verticalCenter: enableSupportCheckBox.verticalCenter
@@ -674,7 +674,7 @@ Item
                 }
             }
 
-            Text
+            Label
             {
                 id: supportExtruderLabel
                 visible: supportExtruderCombobox.visible
@@ -750,7 +750,7 @@ Item
 
             }
 
-            Text
+            Label
             {
                 id: adhesionHelperLabel
                 visible: adhesionCheckBox.visible
@@ -836,12 +836,12 @@ Item
             {
                 id: tipsCell
                 anchors.top: adhesionCheckBox.visible ? adhesionCheckBox.bottom : (enableSupportCheckBox.visible ? supportExtruderCombobox.bottom : infillCellRight.bottom)
-                anchors.topMargin: UM.Theme.getSize("sidebar_margin").height * 2
+                anchors.topMargin: parseInt(UM.Theme.getSize("sidebar_margin").height * 2)
                 anchors.left: parent.left
                 width: parent.width
                 height: tipsText.contentHeight * tipsText.lineCount
 
-                Text
+                Label
                 {
                     id: tipsText
                     anchors.left: parent.left
diff --git a/resources/qml/SidebarTooltip.qml b/resources/qml/SidebarTooltip.qml
index 057bd63203..60d01dd6f6 100644
--- a/resources/qml/SidebarTooltip.qml
+++ b/resources/qml/SidebarTooltip.qml
@@ -43,7 +43,7 @@ UM.PointingRectangle {
         base.opacity = 0;
     }
 
-    Text {
+    Label {
         id: label;
         anchors {
             top: parent.top;
diff --git a/resources/themes/cura-light/theme.json b/resources/themes/cura-light/theme.json
index 96ccd469b6..b41ea96846 100644
--- a/resources/themes/cura-light/theme.json
+++ b/resources/themes/cura-light/theme.json
@@ -17,10 +17,6 @@
             "size": 1.15,
             "family": "Open Sans"
         },
-        "default_little_big": {
-            "size": 1.17,
-            "family": "Open Sans"
-        },
         "default_bold": {
             "size": 1.15,
             "bold": true,