diff --git a/src/gtk/control.cpp b/src/gtk/control.cpp
index 3352965683..f11b6e80ed 100644
--- a/src/gtk/control.cpp
+++ b/src/gtk/control.cpp
@@ -251,6 +251,7 @@ wxControl::GetDefaultAttributesFromGTKWidget(GtkWidget* widget,
     }
     GtkStyleContext* sc = gtk_widget_get_style_context(widget);
     GdkRGBA c;
+    gtk_style_context_set_state(sc, stateFlag);
     gtk_style_context_get_color(sc, stateFlag, &c);
     attr.colFg = wxColour(c);
     gtk_style_context_get_background_color(sc, stateFlag, &c);
@@ -319,7 +320,11 @@ wxSize wxControl::GTKGetPreferredSize(GtkWidget* widget) const
 {
     GtkRequisition req;
 #ifdef __WXGTK3__
+    int w, h;
+    gtk_widget_get_size_request(widget, &w, &h);
+    gtk_widget_set_size_request(widget, -1, -1);
     gtk_widget_get_preferred_size(widget, NULL, &req);
+    gtk_widget_set_size_request(widget, w, h);
 #else
     GTK_WIDGET_GET_CLASS(widget)->size_request(widget, &req);
 #endif
diff --git a/src/gtk/settings.cpp b/src/gtk/settings.cpp
index 0f5f4de5fe..33b0a07752 100644
--- a/src/gtk/settings.cpp
+++ b/src/gtk/settings.cpp
@@ -155,33 +155,39 @@ static GtkWidget* ToolTipWidget()
 static void bg(GtkWidget* widget, GtkStateFlags state, GdkRGBA& gdkRGBA)
 {
     GtkStyleContext* sc = gtk_widget_get_style_context(widget);
+    gtk_style_context_set_state(sc, state);
     gtk_style_context_get_background_color(sc, state, &gdkRGBA);
     if (gdkRGBA.alpha <= 0)
     {
         widget = gtk_widget_get_parent(GTK_WIDGET(ContainerWidget()));
         sc = gtk_widget_get_style_context(widget);
+        gtk_style_context_set_state(sc, state);
         gtk_style_context_get_background_color(sc, state, &gdkRGBA);
     }
 }
 static void fg(GtkWidget* widget, GtkStateFlags state, GdkRGBA& gdkRGBA)
 {
     GtkStyleContext* sc = gtk_widget_get_style_context(widget);
+    gtk_style_context_set_state(sc, state);
     gtk_style_context_get_color(sc, state, &gdkRGBA);
     if (gdkRGBA.alpha <= 0)
     {
         widget = gtk_widget_get_parent(GTK_WIDGET(ContainerWidget()));
         sc = gtk_widget_get_style_context(widget);
+        gtk_style_context_set_state(sc, state);
         gtk_style_context_get_color(sc, state, &gdkRGBA);
     }
 }
 static void border(GtkWidget* widget, GtkStateFlags state, GdkRGBA& gdkRGBA)
 {
     GtkStyleContext* sc = gtk_widget_get_style_context(widget);
+    gtk_style_context_set_state(sc, state);
     gtk_style_context_get_border_color(sc, state, &gdkRGBA);
     if (gdkRGBA.alpha <= 0)
     {
         widget = gtk_widget_get_parent(GTK_WIDGET(ContainerWidget()));
         sc = gtk_widget_get_style_context(widget);
+        gtk_style_context_set_state(sc, state);
         gtk_style_context_get_border_color(sc, state, &gdkRGBA);
     }
 }
@@ -453,6 +459,7 @@ wxFont wxSystemSettingsNative::GetFont( wxSystemFont index )
                 wxNativeFontInfo info;
 #ifdef __WXGTK3__
                 GtkStyleContext* sc = gtk_widget_get_style_context(ButtonWidget());
+                gtk_style_context_set_state(sc, GTK_STATE_FLAG_NORMAL);
                 gtk_style_context_get(sc, GTK_STATE_FLAG_NORMAL,
                     GTK_STYLE_PROPERTY_FONT, &info.description, NULL);
 #else
diff --git a/src/gtk/spinbutt.cpp b/src/gtk/spinbutt.cpp
index a2285fbce3..97f3461af3 100644
--- a/src/gtk/spinbutt.cpp
+++ b/src/gtk/spinbutt.cpp
@@ -196,7 +196,7 @@ wxSize wxSpinButton::DoGetBestSize() const
 #ifdef __WXGTK3__
     GtkStyleContext* sc = gtk_widget_get_style_context(m_widget);
     GtkBorder pad = { 0, 0, 0, 0 };
-    gtk_style_context_get_padding(sc, GtkStateFlags(0), &pad);
+    gtk_style_context_get_padding(sc, gtk_style_context_get_state(sc), &pad);
     best.x -= pad.left + pad.right;
 #else
     gtk_widget_ensure_style(m_widget);
diff --git a/src/gtk/textctrl.cpp b/src/gtk/textctrl.cpp
index 5f4f134da5..8ef85e6f84 100644
--- a/src/gtk/textctrl.cpp
+++ b/src/gtk/textctrl.cpp
@@ -1828,6 +1828,7 @@ void wxTextCtrl::DoApplyWidgetStyle(GtkRcStyle *style)
             gtk_style_context_save(context);
             gtk_style_context_add_class(context, GTK_STYLE_CLASS_VIEW);
         }
+        gtk_style_context_set_state(context, selectedFocused);
         gtk_style_context_get_color(context, selectedFocused, &fg_orig);
         gtk_style_context_get_background_color(context, selectedFocused, &bg_orig);
         if (IsMultiLine())
diff --git a/src/gtk/toplevel.cpp b/src/gtk/toplevel.cpp
index c3d42e8f29..a52dad0461 100644
--- a/src/gtk/toplevel.cpp
+++ b/src/gtk/toplevel.cpp
@@ -1194,6 +1194,14 @@ void wxTopLevelWindowGTK::DoSetSize( int x, int y, int width, int height, int si
     }
 }
 
+extern "C" {
+static gboolean reset_size_request(void* data)
+{
+    gtk_widget_set_size_request(GTK_WIDGET(data), -1, -1);
+    return false;
+}
+}
+
 void wxTopLevelWindowGTK::DoSetClientSize(int width, int height)
 {
     base_type::DoSetClientSize(width, height);
@@ -1202,6 +1210,25 @@ void wxTopLevelWindowGTK::DoSetClientSize(int width, int height)
     // Has to be done after calling base because it calls SetSize,
     // which sets this true
     m_deferShowAllowed = false;
+
+    if (m_wxwindow)
+    {
+        // If window is not resizable or not yet shown, set size request on
+        // client widget, to make it more likely window will get correct size
+        // even if our decorations size cache is incorrect (as it will be before
+        // showing first TLW).
+        if (!gtk_window_get_resizable(GTK_WINDOW(m_widget)))
+        {
+            gtk_widget_set_size_request(m_widget, -1, -1);
+            gtk_widget_set_size_request(m_wxwindow, m_clientWidth, m_clientHeight);
+        }
+        else if (!IsShown())
+        {
+            gtk_widget_set_size_request(m_wxwindow, m_clientWidth, m_clientHeight);
+            // Cancel size request at next idle to allow resizing
+            g_idle_add_full(G_PRIORITY_LOW, reset_size_request, m_wxwindow, NULL);
+        }
+    }
 }
 
 void wxTopLevelWindowGTK::DoGetClientSize( int *width, int *height ) const
diff --git a/src/gtk/win_gtk.cpp b/src/gtk/win_gtk.cpp
index 90ff180ec1..b0f7721f36 100644
--- a/src/gtk/win_gtk.cpp
+++ b/src/gtk/win_gtk.cpp
@@ -192,8 +192,24 @@ static void pizza_remove(GtkContainer* container, GtkWidget* widget)
 }
 
 #ifdef __WXGTK3__
+// Get preferred size of children, to avoid GTK+ warnings complaining
+// that they were size-allocated without asking their preferred size
+static void children_get_preferred_size(const GList* p)
+{
+    for (; p; p = p->next)
+    {
+        const wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
+        if (gtk_widget_get_visible(child->widget))
+        {
+            GtkRequisition req;
+            gtk_widget_get_preferred_size(child->widget, &req, NULL);
+        }
+    }
+}
+
 static void pizza_get_preferred_width(GtkWidget* widget, int* minimum, int* natural)
 {
+    children_get_preferred_size(WX_PIZZA(widget)->m_children);
     *minimum = 0;
     gtk_widget_get_size_request(widget, natural, NULL);
     if (*natural < 0)
@@ -202,6 +218,7 @@ static void pizza_get_preferred_width(GtkWidget* widget, int* minimum, int* natu
 
 static void pizza_get_preferred_height(GtkWidget* widget, int* minimum, int* natural)
 {
+    children_get_preferred_size(WX_PIZZA(widget)->m_children);
     *minimum = 0;
     gtk_widget_get_size_request(widget, NULL, natural);
     if (*natural < 0)
@@ -452,6 +469,7 @@ void wxPizza::get_border(GtkBorder& border)
         else
             sc = gtk_widget_get_style_context(wxGTKPrivate::GetEntryWidget());
 
+        gtk_style_context_set_state(sc, GTK_STATE_FLAG_NORMAL);
         gtk_style_context_get_border(sc, GTK_STATE_FLAG_NORMAL, &border);
 #else // !__WXGTK3__
         GtkStyle* style;
diff --git a/src/gtk/window.cpp b/src/gtk/window.cpp
index a1619c5d0e..8920d55a22 100644
--- a/src/gtk/window.cpp
+++ b/src/gtk/window.cpp
@@ -304,6 +304,7 @@ draw_border(GtkWidget* widget, GdkEventExpose* gdk_event, wxWindow* win)
 #ifdef __WXGTK3__
         GtkStyleContext* sc = gtk_widget_get_style_context(win->m_wxwindow);
         GdkRGBA c;
+        gtk_style_context_set_state(sc, GTK_STATE_FLAG_NORMAL);
         gtk_style_context_get_border_color(sc, GTK_STATE_FLAG_NORMAL, &c);
         gdk_cairo_set_source_rgba(cr, &c);
         cairo_set_line_width(cr, 1);
@@ -4443,6 +4444,7 @@ void wxWindowGTK::GTKApplyStyle(GtkWidget* widget, GtkRcStyle* WXUNUSED_IN_GTK3(
     cairo_pattern_t* pattern = NULL;
     if (m_backgroundColour.IsOk())
     {
+        gtk_style_context_set_state(context, GTK_STATE_FLAG_NORMAL);
         gtk_style_context_get(context,
             GTK_STATE_FLAG_NORMAL, "background-image", &pattern, NULL);
     }
diff --git a/src/propgrid/property.cpp b/src/propgrid/property.cpp
index 5067b8d2e7..72a7a51530 100644
--- a/src/propgrid/property.cpp
+++ b/src/propgrid/property.cpp
@@ -477,13 +477,13 @@ void wxPGProperty::Init()
 
 void wxPGProperty::Init( const wxString& label, const wxString& name )
 {
-    // We really need to check if &label and &name are NULL pointers
-    // (this can if we are called before property grid has been initalized)
+    // wxPG_LABEL reference can be NULL if we are called before property
+    // grid has been initialized
 
-    if ( (&label) != NULL && label != wxPG_LABEL )
+    if ( sm_wxPG_LABEL && label != wxPG_LABEL )
         m_label = label;
 
-    if ( (&name) != NULL && name != wxPG_LABEL )
+    if ( sm_wxPG_LABEL && name != wxPG_LABEL )
         DoSetName( name );
     else
         DoSetName( m_label );