diff --git a/source/uCEFApplicationCore.pas b/source/uCEFApplicationCore.pas
index d9ee9701..a3c95fc4 100644
--- a/source/uCEFApplicationCore.pas
+++ b/source/uCEFApplicationCore.pas
@@ -617,7 +617,9 @@ implementation
 
 uses
   {$IFDEF DELPHI16_UP}
-  System.Math, System.IOUtils, System.SysUtils, {$IFDEF MSWINDOWS}WinApi.TlHelp32, WinApi.PSAPI,{$ENDIF}
+    System.Math, System.IOUtils, System.SysUtils,
+    {$IFDEF MSWINDOWS}WinApi.TlHelp32, WinApi.PSAPI,{$ENDIF}
+    {$IFDEF LINUX}{$IFDEF FMX}Posix.Unistd, Posix.Stdio,{$ENDIF}{$ENDIF}
   {$ELSE}
     Math, {$IFDEF DELPHI14_UP}IOUtils,{$ENDIF} SysUtils,
     {$IFDEF FPC}
@@ -1227,6 +1229,7 @@ begin
   try
     if (aApp <> nil) then
       begin
+        {$WARN SYMBOL_PLATFORM OFF}
         {$IFDEF MSWINDOWS}
           TempArgs.instance := HINSTANCE{$IFDEF FPC}(){$ENDIF};
         {$ELSE}
@@ -1249,7 +1252,7 @@ begin
             {$ENDIF}
           {$ENDIF}
         {$ENDIF}
-
+        {$WARN SYMBOL_PLATFORM ON}
         Result := cef_execute_process(@TempArgs, aApp.Wrap, FWindowsSandboxInfo);
       end;
   except
@@ -1321,6 +1324,7 @@ begin
           {$IFDEF MSWINDOWS}
             TempArgs.instance := HINSTANCE{$IFDEF FPC}(){$ENDIF};
           {$ELSE}
+            {$WARN SYMBOL_PLATFORM OFF}
             {$IFDEF LINUX}
               {$IFDEF FPC}
               TempArgs.argc := argc;
@@ -1339,6 +1343,7 @@ begin
               TempArgs.argv := 0;
               {$ENDIF}
             {$ENDIF}
+            {$WARN SYMBOL_PLATFORM ON}
           {$ENDIF}
 
           if (cef_initialize(@TempArgs, @FAppSettings, aApp.Wrap, FWindowsSandboxInfo) <> 0) then
diff --git a/source/uCEFFMXBufferPanel.pas b/source/uCEFFMXBufferPanel.pas
index b37522e7..572694d1 100644
--- a/source/uCEFFMXBufferPanel.pas
+++ b/source/uCEFFMXBufferPanel.pas
@@ -385,15 +385,15 @@ begin
 end;
 
 function TFMXBufferPanel.GetRealScreenScale(var aResultScale : single) : boolean;
-{$IFDEF DELPHI24_UP}
+{$IFDEF DELPHI24_UP}{$IFDEF MSWINDOWS}
 var
   TempHandle : TCefWindowHandle;
-{$ENDIF}
+{$ENDIF}{$ENDIF}
 begin
   Result       := False;
   aResultScale := 1;
 
-  {$IFDEF DELPHI24_UP}
+  {$IFDEF DELPHI24_UP}{$IFDEF MSWINDOWS}
   TempHandle := GetParentFormHandle;
 
   if (TempHandle <> 0) then
@@ -401,7 +401,7 @@ begin
       Result       := True;
       aResultScale := GetWndScale(TempHandle);
     end;
-  {$ENDIF}
+  {$ENDIF}{$ENDIF}
 end;
 
 function TFMXBufferPanel.GetScreenScale : single;
diff --git a/source/uCEFFMXChromium.pas b/source/uCEFFMXChromium.pas
index 067e5ea8..b94e4154 100644
--- a/source/uCEFFMXChromium.pas
+++ b/source/uCEFFMXChromium.pas
@@ -164,18 +164,18 @@ begin
 end;
 
 function TFMXChromium.GetScreenScale : Single;
-{$IFDEF DELPHI24_UP}
+{$IFDEF DELPHI24_UP}{$IFDEF MSWINDOWS}
 var
   TempHandle : TCefWindowHandle;
-{$ENDIF}
+{$ENDIF}{$ENDIF}
 begin
-  {$IFDEF DELPHI24_UP}
+  {$IFDEF DELPHI24_UP}{$IFDEF MSWINDOWS}
   TempHandle := GetParentFormHandle;
 
   if (TempHandle <> 0) then
     Result := GetWndScale(TempHandle)
    else
-  {$ENDIF}
+  {$ENDIF}{$ENDIF}
     if (GlobalCEFApp <> nil) then
       Result := GlobalCEFApp.DeviceScaleFactor
      else
diff --git a/source/uCEFMiscFunctions.pas b/source/uCEFMiscFunctions.pas
index b7a913cc..292b2631 100644
--- a/source/uCEFMiscFunctions.pas
+++ b/source/uCEFMiscFunctions.pas
@@ -328,6 +328,7 @@ procedure ShowX11Message(const aMessage : string);
 implementation
 
 uses
+  {$IFDEF LINUX}{$IFDEF FMX}Posix.Unistd, Posix.Stdio,{$ENDIF}{$ENDIF}
   uCEFApplicationCore, uCEFSchemeHandlerFactory, uCEFValue,
   uCEFBinaryValue, uCEFStringList;
 
diff --git a/source/uCEFOLEDragAndDrop.pas b/source/uCEFOLEDragAndDrop.pas
index ad33dfd2..6d0a0c5e 100644
--- a/source/uCEFOLEDragAndDrop.pas
+++ b/source/uCEFOLEDragAndDrop.pas
@@ -1,4 +1,4 @@
-// ************************************************************************
+// ************************************************************************
 // ***************************** CEF4Delphi *******************************
 // ************************************************************************
 //
@@ -10,7 +10,7 @@
 // For more information about CEF4Delphi visit :
 //         https://www.briskbard.com/index.php?lang=en&pageid=cef
 //
-//        Copyright © 2021 Salvador Diaz Fau. All rights reserved.
+//        Copyright © 2021 Salvador Diaz Fau. All rights reserved.
 //
 // ************************************************************************
 // ************ vvvv Original license and comments below vvvv *************
diff --git a/update_CEF4Delphi.json b/update_CEF4Delphi.json
index 05cbc01f..ea1e2f4c 100644
--- a/update_CEF4Delphi.json
+++ b/update_CEF4Delphi.json
@@ -2,7 +2,7 @@
   "UpdateLazPackages" : [
     {
       "ForceNotify" : true,
-      "InternalVersion" : 230,
+      "InternalVersion" : 231,
       "Name" : "cef4delphi_lazarus.lpk",
       "Version" : "87.1.13.0"
     }