UPD: Minimal Lazarus version 1.6

src/doublecmd.lpi

@@ -259,7 +259,7 @@ end;"/>
       </Item8>
       <Item9>
         <PackageName Value="LCL"/>
-        <MinVersion Major="1" Valid="True"/>
+        <MinVersion Major="1" Minor="6" Valid="True"/>
       </Item9>
       <Item10>
         <PackageName Value="SynEdit"/>

src/fmain.pas

@@ -860,7 +860,7 @@ uses
   uDragDropEx, uKeyboard, uFileSystemFileSource, fViewOperations, uMultiListFileSource,
   uFileSourceOperationTypes, uFileSourceCopyOperation, uFileSourceMoveOperation,
   uFileSourceProperty, uFileSourceExecuteOperation, uArchiveFileSource, uThumbFileView,
-  uShellExecute, fSymLink, fHardLink, uExceptions, uUniqueInstance, Clipbrd,
+  uShellExecute, fSymLink, fHardLink, uExceptions, uUniqueInstance, Clipbrd, ShellCtrls,
   uFileSourceOperationOptionsUI, uDebug, uHotkeyManager, uFileSourceUtil, uTempFileSystemFileSource,
   Laz2_XMLRead, DCOSUtils, DCStrUtils, fOptions, fOptionsFrame, fOptionsToolbar, uClassesEx,
   uHotDir, uFileSorting, DCBasicTypes, foptionsDirectoryHotlist, uConnectionManager
@@ -869,12 +869,6 @@ uses
   {$ELSE}
   , uColumnsFileView
   {$ENDIF}
-  // TODO: remove when switch to Lazarus 1.6
-  {$IF (lcl_fullversion < 1060000)}
-  , uShellCtrls
-  {$ELSE}
-  , ShellCtrls
-  {$ENDIF}
   ;
 
 const