diff --git a/gui/wxpython/core/settings.py b/gui/wxpython/core/settings.py
index 5f75a77ee54..e4c961607fb 100644
--- a/gui/wxpython/core/settings.py
+++ b/gui/wxpython/core/settings.py
@@ -143,6 +143,7 @@ def _defaultSettings(self):
                         globalvar.MAP_WINDOW_SIZE[0],
                         globalvar.MAP_WINDOW_SIZE[1],
                     ),
+                    "dimSingleWindow": "1,1,1,1",
                 },
                 # workspace
                 "workspace": {
diff --git a/gui/wxpython/gui_core/preferences.py b/gui/wxpython/gui_core/preferences.py
index 50c2c6f3334..2fbc1aefa04 100644
--- a/gui/wxpython/gui_core/preferences.py
+++ b/gui/wxpython/gui_core/preferences.py
@@ -1830,32 +1830,47 @@ def _updateSettings(self):
         #
         # update default window dimension
         #
-        if (
-            self.settings.Get(group="general", key="defWindowPos", subkey="enabled")
-            is True
-        ):
-            dim = ""
-            # layer manager
+        windows_pos = self.settings.Get(
+            group="general",
+            key="defWindowPos",
+            subkey="enabled",
+        )
+        single_window = self.settings.Get(
+            group="appearance",
+            key="singleWindow",
+            subkey="enabled",
+        )
+        if windows_pos:
+            # get dimension of main window
             pos = self.parent.GetPosition()
             size = self.parent.GetSize()
-            dim = "%d,%d,%d,%d" % (pos[0], pos[1], size[0], size[1])
-            # opened displays
+            dim = f"{pos[0]},{pos[1]},{size[0]},{size[1]}"
+
+            # extend dimension by dimensions of opened displays
             for mapdisp in self._giface.GetAllMapDisplays():
                 pos = mapdisp.GetPosition()
                 size = mapdisp.GetSize()
 
                 # window size must be larger than zero, not minimized
-                # when mapdisp is inside single window (panel has no IsIconized), don't save dim
-                if (
-                    hasattr(mapdisp, "IsIconized")
-                    and not mapdisp.IsIconized()
-                    and (size[0] > 0 and size[1] > 0)
+                # do not save dim when mapdisp is docked within single window
+                if (not mapdisp.IsDockable() or not mapdisp.IsDocked()) and (
+                    size[0] > 0 and size[1] > 0
                 ):
-                    dim += ",%d,%d,%d,%d" % (pos[0], pos[1], size[0], size[1])
+                    dim += f",{pos[0]},{pos[1]},{size[0]},{size[1]}"
 
-            self.settings.Set(
-                group="general", key="defWindowPos", subkey="dim", value=dim
-            )
+            if single_window:
+                # single window mode
+                self.settings.Set(
+                    group="general",
+                    key="defWindowPos",
+                    subkey="dimSingleWindow",
+                    value=dim,
+                )
+            else:
+                # multi window mode
+                self.settings.Set(
+                    group="general", key="defWindowPos", subkey="dim", value=dim
+                )
 
         return True
 
diff --git a/gui/wxpython/main_window/frame.py b/gui/wxpython/main_window/frame.py
index eee07982bf4..5d7a46de8da 100644
--- a/gui/wxpython/main_window/frame.py
+++ b/gui/wxpython/main_window/frame.py
@@ -103,7 +103,7 @@ def __init__(
         id=wx.ID_ANY,
         title=None,
         workspace=None,
-        size=wx.Display().GetGeometry().GetSize(),
+        size=wx.GetClientDisplayRect().GetSize(),
         style=wx.DEFAULT_FRAME_STYLE,
         **kwargs,
     ):
@@ -179,30 +179,32 @@ def show_menu_errors(messages):
 
         # use default window layout ?
         if UserSettings.Get(group="general", key="defWindowPos", subkey="enabled"):
-            dim = UserSettings.Get(group="general", key="defWindowPos", subkey="dim")
-            try:
-                x, y = map(int, dim.split(",")[0:2])
-                w, h = map(int, dim.split(",")[2:4])
-                client_disp = wx.ClientDisplayRect()
-                if x == 1:
-                    # Get client display x offset (OS panel)
-                    x = client_disp[0]
-                if y == 1:
-                    # Get client display y offset (OS panel)
-                    y = client_disp[1]
-                self.SetPosition((x, y))
-                self.SetSize((w, h))
-            except Exception:
-                pass
-            self.Layout()
-            if w <= globalvar.GM_WINDOW_SIZE[0] or h <= globalvar.GM_WINDOW_SIZE[1]:
-                self.Fit()
+            single_window_dim = {
+                "group": "general",
+                "key": "defWindowPos",
+                "subkey": "dimSingleWindow",
+            }
+            dim = UserSettings.Get(**single_window_dim)
+            default_dim = UserSettings.Get(**single_window_dim, settings_type="default")
+
+            if dim != default_dim:
+                try:
+                    x, y, w, h = map(int, dim.split(",")[:4])
+                    client_disp = wx.ClientDisplayRect()
+                    if x == 1:
+                        # Get client display x offset (OS panel)
+                        x = client_disp[0]
+                    if y == 1:
+                        # Get client display y offset (OS panel)
+                        y = client_disp[1]
+                    self.SetPosition((x, y))
+                    self.SetSize((w, h))
+                except Exception:
+                    pass
+            else:
+                self.Maximize(True)
         else:
-            self.Layout()
-            self.Fit()
-            # does center (of screen) make sense for lmgr?
-            self.Centre()
-
+            self.Maximize(True)
         self.Show()
 
         # load workspace file if requested