diff --git a/spinetoolbox/ui/jump_properties.py b/spinetoolbox/ui/jump_properties.py
index 718f0d6e6..beb29ec04 100644
--- a/spinetoolbox/ui/jump_properties.py
+++ b/spinetoolbox/ui/jump_properties.py
@@ -26,10 +26,11 @@
     QFont, QFontDatabase, QGradient, QIcon,
     QImage, QKeySequence, QLinearGradient, QPainter,
     QPalette, QPixmap, QRadialGradient, QTransform)
-from PySide6.QtWidgets import (QAbstractItemView, QApplication, QComboBox, QGridLayout,
-    QGroupBox, QHBoxLayout, QHeaderView, QPushButton,
-    QRadioButton, QScrollArea, QSizePolicy, QSpacerItem,
-    QToolButton, QTreeView, QVBoxLayout, QWidget)
+from PySide6.QtWidgets import (QAbstractItemView, QApplication, QComboBox, QFrame,
+    QGridLayout, QGroupBox, QHBoxLayout, QHeaderView,
+    QPushButton, QRadioButton, QScrollArea, QSizePolicy,
+    QSpacerItem, QToolButton, QTreeView, QVBoxLayout,
+    QWidget)
 
 from spinetoolbox.widgets.code_text_edit import CodeTextEdit
 from spinetoolbox import resources_icons_rc
@@ -39,16 +40,19 @@ def setupUi(self, Form):
         if not Form.objectName():
             Form.setObjectName(u"Form")
         Form.resize(307, 400)
+        Form.setStyleSheet(u"QScrollArea { background: transparent; }\n"
+"QScrollArea > QWidget > QWidget { background: transparent; }")
         self.verticalLayout_3 = QVBoxLayout(Form)
         self.verticalLayout_3.setSpacing(0)
         self.verticalLayout_3.setObjectName(u"verticalLayout_3")
         self.verticalLayout_3.setContentsMargins(0, 0, 0, 0)
         self.scrollArea = QScrollArea(Form)
         self.scrollArea.setObjectName(u"scrollArea")
+        self.scrollArea.setFrameShape(QFrame.Shape.NoFrame)
         self.scrollArea.setWidgetResizable(True)
         self.scrollAreaWidgetContents = QWidget()
         self.scrollAreaWidgetContents.setObjectName(u"scrollAreaWidgetContents")
-        self.scrollAreaWidgetContents.setGeometry(QRect(0, 0, 305, 398))
+        self.scrollAreaWidgetContents.setGeometry(QRect(0, 0, 307, 400))
         self.verticalLayout = QVBoxLayout(self.scrollAreaWidgetContents)
         self.verticalLayout.setSpacing(0)
         self.verticalLayout.setObjectName(u"verticalLayout")
diff --git a/spinetoolbox/ui/jump_properties.ui b/spinetoolbox/ui/jump_properties.ui
index 562bfbfda..666654049 100644
--- a/spinetoolbox/ui/jump_properties.ui
+++ b/spinetoolbox/ui/jump_properties.ui
@@ -26,6 +26,10 @@
   <property name="windowTitle">
    <string>Form</string>
   </property>
+  <property name="styleSheet">
+   <string notr="true">QScrollArea { background: transparent; }
+QScrollArea &gt; QWidget &gt; QWidget { background: transparent; }</string>
+  </property>
   <layout class="QVBoxLayout" name="verticalLayout_3">
    <property name="spacing">
     <number>0</number>
@@ -44,6 +48,9 @@
    </property>
    <item>
     <widget class="QScrollArea" name="scrollArea">
+     <property name="frameShape">
+      <enum>QFrame::Shape::NoFrame</enum>
+     </property>
      <property name="widgetResizable">
       <bool>true</bool>
      </property>
@@ -52,8 +59,8 @@
        <rect>
         <x>0</x>
         <y>0</y>
-        <width>305</width>
-        <height>398</height>
+        <width>307</width>
+        <height>400</height>
        </rect>
       </property>
       <layout class="QVBoxLayout" name="verticalLayout">
@@ -157,7 +164,7 @@
               <string>...</string>
              </property>
              <property name="icon">
-              <iconset resource="resources/resources_icons.qrc">
+              <iconset>
                <normaloff>:/icons/file-upload.svg</normaloff>:/icons/file-upload.svg</iconset>
              </property>
             </widget>
diff --git a/spinetoolbox/ui/link_properties.py b/spinetoolbox/ui/link_properties.py
index 55a76298a..5aa369177 100644
--- a/spinetoolbox/ui/link_properties.py
+++ b/spinetoolbox/ui/link_properties.py
@@ -39,16 +39,20 @@ def setupUi(self, Form):
         if not Form.objectName():
             Form.setObjectName(u"Form")
         Form.resize(362, 404)
+        Form.setStyleSheet(u"QScrollArea { background: transparent; }\n"
+"QScrollArea > QWidget > QWidget { background: transparent; }")
         self.verticalLayout_3 = QVBoxLayout(Form)
         self.verticalLayout_3.setSpacing(0)
         self.verticalLayout_3.setObjectName(u"verticalLayout_3")
         self.verticalLayout_3.setContentsMargins(0, 0, 0, 0)
         self.scrollArea = QScrollArea(Form)
         self.scrollArea.setObjectName(u"scrollArea")
+        self.scrollArea.setFrameShape(QFrame.Shape.NoFrame)
         self.scrollArea.setWidgetResizable(True)
         self.scrollAreaWidgetContents = QWidget()
         self.scrollAreaWidgetContents.setObjectName(u"scrollAreaWidgetContents")
-        self.scrollAreaWidgetContents.setGeometry(QRect(0, 0, 360, 402))
+        self.scrollAreaWidgetContents.setGeometry(QRect(0, 0, 362, 404))
+        self.scrollAreaWidgetContents.setAutoFillBackground(False)
         self.verticalLayout = QVBoxLayout(self.scrollAreaWidgetContents)
         self.verticalLayout.setSpacing(0)
         self.verticalLayout.setObjectName(u"verticalLayout")
diff --git a/spinetoolbox/ui/link_properties.ui b/spinetoolbox/ui/link_properties.ui
index 1c91c7b69..976159286 100644
--- a/spinetoolbox/ui/link_properties.ui
+++ b/spinetoolbox/ui/link_properties.ui
@@ -26,6 +26,10 @@
   <property name="windowTitle">
    <string>Form</string>
   </property>
+  <property name="styleSheet">
+   <string notr="true">QScrollArea { background: transparent; }
+QScrollArea &gt; QWidget &gt; QWidget { background: transparent; }</string>
+  </property>
   <layout class="QVBoxLayout" name="verticalLayout_3">
    <property name="spacing">
     <number>0</number>
@@ -44,6 +48,9 @@
    </property>
    <item>
     <widget class="QScrollArea" name="scrollArea">
+     <property name="frameShape">
+      <enum>QFrame::Shape::NoFrame</enum>
+     </property>
      <property name="widgetResizable">
       <bool>true</bool>
      </property>
@@ -52,10 +59,13 @@
        <rect>
         <x>0</x>
         <y>0</y>
-        <width>360</width>
-        <height>402</height>
+        <width>362</width>
+        <height>404</height>
        </rect>
       </property>
+      <property name="autoFillBackground">
+       <bool>false</bool>
+      </property>
       <layout class="QVBoxLayout" name="verticalLayout">
        <property name="spacing">
         <number>0</number>
diff --git a/spinetoolbox/ui/mainwindow.py b/spinetoolbox/ui/mainwindow.py
index 79c337f0b..1e716bc71 100644
--- a/spinetoolbox/ui/mainwindow.py
+++ b/spinetoolbox/ui/mainwindow.py
@@ -340,7 +340,7 @@ def setupUi(self, MainWindow):
         self.tab_no_selection.setObjectName(u"tab_no_selection")
         self.verticalLayout_14 = QVBoxLayout(self.tab_no_selection)
         self.verticalLayout_14.setObjectName(u"verticalLayout_14")
-        self.verticalLayout_14.setContentsMargins(6, 6, 6, 6)
+        self.verticalLayout_14.setContentsMargins(0, 0, 0, 0)
         self.label_no_selection = QLabel(self.tab_no_selection)
         self.label_no_selection.setObjectName(u"label_no_selection")
         self.label_no_selection.setAlignment(Qt.AlignmentFlag.AlignCenter)
diff --git a/spinetoolbox/ui/mainwindow.ui b/spinetoolbox/ui/mainwindow.ui
index 6d14f4849..6563a0165 100644
--- a/spinetoolbox/ui/mainwindow.ui
+++ b/spinetoolbox/ui/mainwindow.ui
@@ -390,16 +390,16 @@
         </attribute>
         <layout class="QVBoxLayout" name="verticalLayout_14">
          <property name="leftMargin">
-          <number>6</number>
+          <number>0</number>
          </property>
          <property name="topMargin">
-          <number>6</number>
+          <number>0</number>
          </property>
          <property name="rightMargin">
-          <number>6</number>
+          <number>0</number>
          </property>
          <property name="bottomMargin">
-          <number>6</number>
+          <number>0</number>
          </property>
          <item>
           <widget class="QLabel" name="label_no_selection">
diff --git a/spinetoolbox/widgets/properties_widget.py b/spinetoolbox/widgets/properties_widget.py
index 04009f440..2f9328b30 100644
--- a/spinetoolbox/widgets/properties_widget.py
+++ b/spinetoolbox/widgets/properties_widget.py
@@ -57,16 +57,20 @@ def set_color_and_icon(self, base_color, icon=None):
         bnw_pixmap = QPixmap(icon)
         self._pixmap = QPixmap(bnw_pixmap.size())
         self._pixmap.fill(self._fg_color)
-        self._pixmap.setMask(bnw_pixmap.createMaskFromColor(Qt.transparent))
+        self._pixmap.setMask(bnw_pixmap.createMaskFromColor(Qt.GlobalColor.transparent))
 
     def eventFilter(self, obj, ev):
-        if ev.type() == QEvent.Paint:
+        if ev.type() == QEvent.Type.Paint:
             painter = QPainter(obj)
             painter.fillRect(obj.rect(), QColor(255, 255, 255, 180))
         return super().eventFilter(obj, ev)
 
     def paintEvent(self, ev):
-        """Paints background"""
+        """Paints background.
+
+        Note: The backgrounds of the properties widget's QScrollArea
+        and the scrollAreaWidgetContents QWidget are set to transparent in stylesheets.
+        """
         settings = self._toolbox.qsettings()
         if settings.value("appSettings/colorPropertiesWidgets", defaultValue="false") == "false":
             super().paintEvent(ev)
@@ -80,10 +84,10 @@ def paintEvent(self, ev):
         new_transparent_widgets -= self._transparent_widgets
         self._transparent_widgets |= new_transparent_widgets
         for widget in new_transparent_widgets:
-            widget.setAttribute(Qt.WA_NoSystemBackground)
+            widget.setAttribute(Qt.WidgetAttribute.WA_NoSystemBackground)
             widget.installEventFilter(self)
             try:
-                widget.viewport().setAttribute(Qt.WA_TranslucentBackground)
+                widget.viewport().setAttribute(Qt.WidgetAttribute.WA_TranslucentBackground)
             except AttributeError:
                 pass
         rect = self.rect()