hhctrl.ocx: Issue a fixme if asked for unsupported toolbar buttons.
diff --git a/dlls/hhctrl.ocx/help.c b/dlls/hhctrl.ocx/help.c
index d52939d..7bde256 100644
--- a/dlls/hhctrl.ocx/help.c
+++ b/dlls/hhctrl.ocx/help.c
@@ -785,6 +785,7 @@
     int nHistBitmaps = 0, nStdBitmaps = 0, nHHBitmaps = 0;
     HWND hToolbar = pHHInfo->WinType.hwndToolBar;
     TBADDBITMAP tbAB;
+    DWORD unsupported;
 
     /* Common bitmaps */
     tbAB.hInst = HINST_COMMCTRL;
@@ -799,6 +800,14 @@
 
     *pdwNumButtons = 0;
 
+    unsupported = dwButtonFlags & (HHWIN_BUTTON_BROWSE_FWD |
+        HHWIN_BUTTON_BROWSE_BCK | HHWIN_BUTTON_NOTES | HHWIN_BUTTON_CONTENTS |
+        HHWIN_BUTTON_INDEX | HHWIN_BUTTON_SEARCH | HHWIN_BUTTON_HISTORY |
+        HHWIN_BUTTON_FAVORITES | HHWIN_BUTTON_JUMP1 | HHWIN_BUTTON_JUMP2 |
+        HHWIN_BUTTON_ZOOM | HHWIN_BUTTON_TOC_NEXT | HHWIN_BUTTON_TOC_PREV);
+    if (unsupported)
+        FIXME("got asked for unsupported buttons: %06x\n", unsupported);
+
     if (dwButtonFlags & HHWIN_BUTTON_EXPAND)
     {
         TB_AddButton(pButtons, (*pdwNumButtons)++, IDTB_EXPAND, nHistBitmaps + HIST_VIEWTREE);