Index: ZPreview/src/Delphi/F_PE_Hex.dfm
==================================================================
--- ZPreview/src/Delphi/F_PE_Hex.dfm
+++ ZPreview/src/Delphi/F_PE_Hex.dfm
@@ -18,10 +18,11 @@
     Left = 0
     Top = 0
     Width = 401
     Height = 282
     Align = alClient
+    Color = clBtnFace
     ParentColor = False
     OnPaint = pbxPreviewPaint
     ExplicitLeft = 120
     ExplicitTop = 56
     ExplicitWidth = 105

Index: ZPreview/src/Delphi/F_PE_Hex.pas
==================================================================
--- ZPreview/src/Delphi/F_PE_Hex.pas
+++ ZPreview/src/Delphi/F_PE_Hex.pas
@@ -76,10 +76,16 @@
 var
   Canvas: TCanvas;
 begin
   {$MESSAGE WARN 'TODO: TfrmPEHex.pbxPreviewPaint — MCO 18-02-2015'}
   // TODO: check whether anything has changed since last time?
+  // TODO: differentiate between context changes and content changes
+  //        (context being the width, height, font; content being the file (name),
+  //        position, selection start and end, etc).
+  //       Context change means we need to recalculate everything, then redraw;
+  //        content change means we don't need to recalculate everything, just
+  //        the position and actual contents.
   if not Assigned(FBitmap)
     or (pbxPreview.ClientWidth <> FBitmap.Width)
     or (pbxPreview.ClientHeight <> FBitmap.Height)
     or CompareMem(@FCurrLayout, @FPrevLayout, SizeOf(TLayoutInfo))
   then begin