diff --git a/src/ui/qgspropertycolorassistantwidget.ui b/src/ui/qgspropertycolorassistantwidget.ui
index ef527ae7a77..17518a421a5 100644
--- a/src/ui/qgspropertycolorassistantwidget.ui
+++ b/src/ui/qgspropertycolorassistantwidget.ui
@@ -19,7 +19,7 @@
      <property name="sizeHint" stdset="0">
       <size>
        <width>20</width>
-       <height>40</height>
+       <height>0</height>
       </size>
      </property>
     </spacer>
diff --git a/src/ui/qgspropertygenericnumericassistantwidget.ui b/src/ui/qgspropertygenericnumericassistantwidget.ui
index a795e3d831e..8198c3aa8f2 100644
--- a/src/ui/qgspropertygenericnumericassistantwidget.ui
+++ b/src/ui/qgspropertygenericnumericassistantwidget.ui
@@ -102,7 +102,7 @@
      <property name="sizeHint" stdset="0">
       <size>
        <width>20</width>
-       <height>40</height>
+       <height>0</height>
       </size>
      </property>
     </spacer>
diff --git a/src/ui/qgspropertysizeassistantwidget.ui b/src/ui/qgspropertysizeassistantwidget.ui
index 1bbb7bc7f0c..477e5b09344 100644
--- a/src/ui/qgspropertysizeassistantwidget.ui
+++ b/src/ui/qgspropertysizeassistantwidget.ui
@@ -112,7 +112,7 @@
      <property name="sizeHint" stdset="0">
       <size>
        <width>20</width>
-       <height>40</height>
+       <height>0</height>
       </size>
      </property>
     </spacer>
@@ -126,6 +126,13 @@
    <header>qgsdoublespinbox.h</header>
   </customwidget>
  </customwidgets>
+ <tabstops>
+  <tabstop>minSizeSpinBox</tabstop>
+  <tabstop>maxSizeSpinBox</tabstop>
+  <tabstop>scaleMethodComboBox</tabstop>
+  <tabstop>exponentSpinBox</tabstop>
+  <tabstop>nullSizeSpinBox</tabstop>
+ </tabstops>
  <resources/>
  <connections/>
 </ui>