select form field of links use button with window.open to go to page

Question

I have a form field that has a list of vendors pages. The value of each is the url for the exact page I want to send customers to. Some users are just getting a page refresh instead of the browser opening a new window and going to the address.

<label for="Liners">Liner Tray Sizes: 125 - 18</label>
<form name="jump1">
<select name="Liners">
   <option value="#">Choose an Availability Quick Link</option>
   <option value="http://www.agristarts.com/index.cfm/fuseaction/plants.availability/index. htm"  > Agristarts</option>
   <option value="http://www.ag3inc.com/Availability.asp"  > AG3</option>
   <option value="http://www.arcferns.com/Availability.html"  > ARC Ferns</option> 
</select>
<button type="submit" class="btn btn-primary" onclick="window.open(Liners.value, 'newtab')">Go</button>
</form>

I have checked the browsers settings on the computers having issues, Java Script is enabled, and i white-listed the site as well. Is there something in my code that is wrong? This was working before on a previous version of the site, so I just copied it over.