Can not find attribute on firefox

Hi
Currently, I use customized code to find object
But on firefox , I can not find it. I see log file, count of htmlCollection =0
 public void DeleteSheet_CodedStep()
        {
            object sheetName = GetExtractedValue("SheetName");
             
            Assert.IsNotNull(sheetName, "variable SheetName on calling method is not defined");
             
            string sheetNameString =  (sheetName as string).Trim();
             
            Log.WriteLine(string.Format("{0} variable is defined", sheetNameString));     
             
            sheetNameString = Utility.HandleLongString(sheetNameString);
            
            Log.WriteLine(sheetNameString);
            
            sheetNameString = Utility.HtmlEncode(sheetNameString);
            
            Log.WriteLine(sheetNameString);   
            
            HtmlDiv htmlDiv = Find.ById<HtmlDiv>("dnn_ctr431_ViewMediaResource_UP");  
            
            Log.WriteLine("htmlDiv"+htmlDiv);
            
            //Add find on firefox until find out result
   /*         if (ActiveBrowser.BrowserType == BrowserType.FireFox || ActiveBrowser.BrowserType == BrowserType.Chrome )
            {
                while (htmlDiv == null)
                {
                    ActiveBrowser.RefreshDomTree();
                    htmlDiv = Find.ById<HtmlDiv>("dnn_ctr431_ViewMediaResource_UP");
                }
            }
    */
            
            IList<HtmlDiv> htmlDivsCollection = htmlDiv.Find.AllByAttributes<HtmlDiv>("class=body-component");

    /*        if (ActiveBrowser.BrowserType == BrowserType.FireFox )
            {
                while (htmlDivsCollection.Count() == 0)
                {
                    ActiveBrowser.RefreshDomTree();
                    htmlDivsCollection = htmlDiv.Find.AllByAttributes<HtmlDiv>("class=body-component");
                }
            }
    */
            
            Log.WriteLine(string.Format("{0} html div count found", htmlDivsCollection.Count.ToString()));
            
            foreach(HtmlDiv listItem in htmlDivsCollection)
            {
                IList<HtmlDiv> contentColletion = listItem.Find.AllByAttributes<HtmlDiv>("class=body-component-content");
                
                Log.WriteLine(contentColletion[0].TextContent);
                
                if (String.Compare(sheetNameString, contentColletion[0].TextContent) == 0)
                {
                    Log.WriteLine("mediaSheet found");
                    
                    IList<HtmlControl> default_sheet = listItem.Find.AllByAttributes<HtmlControl>("class=body-component-menu-delete");
               
                    if(default_sheet != null && default_sheet.Count > 0)
                    {
                        Log.WriteLine(string.Format("language tile object {0} deleted", sheetNameString));
                        listItem.MouseHover();
                        default_sheet[0].MouseClick();
                    }
                    
                    break;
                } 
Please refer attachment
Thanks so much