7cc2de4244e51395682085c51e3fe27ba9f1cfc5
chmalee
  Fri Apr 3 16:15:20 2026 -0700
Items with a tooltip but no name now get their mouseovers to show up correctly, refs #37322

diff --git src/hg/hgTracks/imageV2.c src/hg/hgTracks/imageV2.c
index 75224207156..ca7adb0023d 100644
--- src/hg/hgTracks/imageV2.c
+++ src/hg/hgTracks/imageV2.c
@@ -1852,30 +1852,35 @@
         if (cfgOptionBooleanDefault("showMouseovers", FALSE))
             {
             if (isNotEmpty(item->tooltip))
                 hPrintf(" title='%s' data-tooltip='%s'", encodedString, attributeEncode(item->tooltip));
             else
                 hPrintf(" TITLE='%s'", encodedString);
             }
         else
             {
             // for TITLEs, which we use for mouseOvers,  since they can't have HTML in
             // them, we substitute a unicode new line for <br> after we've encoded it.
             // This is stop-gap until we start doing mouseOvers entirely in Javascript
             hPrintf(" TITLE='%s'", replaceChars(encodedString,"&#x3C;br&#x3E;", "&#8232;"));
             }
         }
+    else if (isNotEmpty(item->tooltip) && cfgOptionBooleanDefault("showMouseovers", FALSE))
+        {
+        // some items have no title string (no item name) but do have tooltips
+        hPrintf(" data-tooltip='%s'", attributeEncode(item->tooltip));
+        }
     if (item->id != NULL)
         hPrintf(" id='%s'", item->id);
     hPrintf(">" );
     }
 hPrintf("</MAP>\n");
 return TRUE;
 }
 
 static void imageDraw(struct imgBox *imgBox,struct imgTrack *imgTrack,struct imgSlice *slice,
                       char *name,int offsetX,int offsetY,boolean useMap)
 // writes an image as HTML
 {
 if (slice->parentImg && slice->parentImg->file != NULL)
     {
     hPrintf("  <IMG id='img_%s' src='%s' style='left:-%dpx; top: -%dpx;'",