diff --git a/components/chmhelp/packages/help/lazhelpchm.pas b/components/chmhelp/packages/help/lazhelpchm.pas
index 81df350068..809d5224f5 100644
--- a/components/chmhelp/packages/help/lazhelpchm.pas
+++ b/components/chmhelp/packages/help/lazhelpchm.pas
@@ -162,11 +162,15 @@ begin
   end;
 
   SplitURL(Node.URL,URLScheme,URLPath,URLParams);
-  CHMFilename:=SetDirSeparators(URLPath);
+  CHMFilename:=CleanAndExpandFilename(URLPath);
   if not FileExistsUTF8(CHMFilename) then begin
     ErrMsg:='chm file "'+CHMFilename+'" not found';
     exit;
   end;
+  if DirPathExists(CHMFilename) then begin
+    ErrMsg:='invalid chm file "'+CHMFilename+'"';
+    exit;
+  end;
 
   SubPath:='';
   if (URLParams<>'') and (URLParams[1]='?') then
@@ -205,12 +209,6 @@ begin
       if s<>'' then Path:=s;
     end;
 
-    {$IFDEF darwin}
-    // search exe in application bundle
-    if DirectoryExistsUTF8(Path+'.app') then
-      Path:=Path+'.app/Contents/MacOS/'+ExtractFileName(Path);
-    {$ENDIF}
-
     if not FileExistsUTF8(Path) then begin
       ErrMsg:='The chm viewer program lhelp was not found at "'+Path+'"';
       exit;
@@ -231,6 +229,7 @@ begin
   else
     ErrMsg:='Something is wrong with lhelp';
   end;
+  debugln(['TLHelpConnector.ShowNode error: ',ErrMsg]);
 end;
 
 procedure TLHelpConnector.Assign(Source: TPersistent);
diff --git a/components/chmhelp/packages/help/lhelpcontrol.pas b/components/chmhelp/packages/help/lhelpcontrol.pas
index c03e1066dd..1476365851 100644
--- a/components/chmhelp/packages/help/lhelpcontrol.pas
+++ b/components/chmhelp/packages/help/lhelpcontrol.pas
@@ -23,7 +23,7 @@ uses
   {$IFDEF STALE_PIPE_WORKAROUND}
   BaseUnix,
   {$ENDIF}
-  Classes, SysUtils, FileUtil, SimpleIPC, UTF8Process;
+  Classes, SysUtils, FileUtil, LazLogger, SimpleIPC, process, UTF8Process;
 
 type
   TRequestType = (rtFile, rtUrl, rtContext);
@@ -172,6 +172,7 @@ function TLHelpConnection.StartHelpServer(NameForServer: String;
   ServerEXE: String): Boolean;
 var
   X: Integer;
+  Cmd: String;
 begin
   Result := False;
 
@@ -183,8 +184,21 @@ begin
   fServerOut.Active := False;
   fServerOut.ServerID := NameForServer;
   if not ServerRunning then begin
+    Cmd:= ServerExe + ' --ipcname ' + NameForServer;
+    {$IFDEF darwin}
+    if DirectoryExistsUTF8(ServerEXE+'.app') then
+      ServerEXE+='.app';
+    debugln(['TLHelpConnection.StartHelpServer ',ServerEXE]);
+    if DirectoryExistsUTF8(ServerEXE) then begin
+      // application bundle
+      // to put lhelp into the foreground, use "open -n"
+      Cmd:='/usr/bin/open -n '+ServerEXE+' --args --ipcname ' + NameForServer
+    end;
+    DebugLn(['TLHelpConnection.StartHelpServer ',cmd]);
+    {$ENDIF}
     with TProcessUTF8.Create(nil) do begin
-      CommandLine := ServerExe + ' --ipcname ' + NameForServer;
+      ShowWindow:=swoShowNormal;
+      CommandLine := Cmd;
       Execute;
       Free;
     end;