<select class="form-dropdown validate[required]" id="input_70" name="q70_ethnicity" style="width:150px" data-component="dropdown" required="">
             <option data-calcvalue="0" value="">  </option>
             <option data-calcvalue="315236000" value="White British"> White British </option>
             <option data-calcvalue="315237009" value="White Irish"> White Irish </option>
             <option data-calcvalue="40124002" value="Other White Ethnicity"> Other White Ethnicity </option>
             <option data-calcvalue="185988007" value="Black Caribbean"> Black Caribbean </option>
             <option data-calcvalue="18167009" value="Black African"> Black African </option>
             <option data-calcvalue="315279003" value="Other Black Ethnicity"> Other Black Ethnicity </option>
             <option data-calcvalue="186003008" value="Bangladeshi"> Bangladeshi </option>
             <option data-calcvalue="414481008" value="Indian"> Indian </option>
             <option data-calcvalue="1860062003" value="Pakistani"> Pakistani </option>
             <option data-calcvalue="90087003" value="Arabic"> Arabic </option>
             <option data-calcvalue="33897005" value="Chinese"> Chinese </option>
             <option data-calcvalue="372148003" value="Other ethnic group"> Other ethnic group </option>
             <option data-calcvalue="1024701000000100" value="Prefer not to say"> Prefer not to say </option>
           </select>

I am trying to9 use a web site that includes the following code in the page source: <div id="cid_70" class="form-input jf-required"> <select class="form-dropdown validate[required]" id="input_70" name="q70_ethnicity" style="width:150px" data-component="dropdown" required=""> <option data-calcvalue="0" value=""> </option> <option data-calcvalue="315236000" value="White British"> White British </option> <option data-calcvalue="315237009" value="White Irish"> White Irish </option> <option data-calcvalue="40124002" value="Other White Ethnicity"> Other White Ethnicity </option> <option data-calcvalue="185988007" value="Black Caribbean"> Black Caribbean </option> <option data-calcvalue="18167009" value="Black African"> Black African </option> <option data-calcvalue="315279003" value="Other Black Ethnicity"> Other Black Ethnicity </option> <option data-calcvalue="186003008" value="Bangladeshi"> Bangladeshi </option> <option data-calcvalue="414481008" value="Indian"> Indian </option> <option data-calcvalue="1860062003" value="Pakistani"> Pakistani </option> <option data-calcvalue="90087003" value="Arabic"> Arabic </option> <option data-calcvalue="33897005" value="Chinese"> Chinese </option> <option data-calcvalue="372148003" value="Other ethnic group"> Other ethnic group </option> <option data-calcvalue="1024701000000100" value="Prefer not to say"> Prefer not to say </option> </select> </div> In Firefox on my Macbook Pro and on y iPhone, his drop down is empty and the above code does not show in the source. If I use Safari, on my Mac, the code above is present and the drop down works as expected. Is this a construct not supported by Firefox?