找到：mobile/templates/library/page_footer.lbi

修改：

  {if $pname=='goods'}
  <p><a href="/goods.php?id={$goods_info.goods_id}&from_mobile=1" style="color:#D14147">切换电脑版</a></p>
  {else}
  <p><a href="/?from_mobile=1" style="color:#D14147">切换电脑版</a></p>
  {/if}

为
  {if $pname=='goods'}
  <p><a href="{$main_path}/goods.php?id={$goods_info.goods_id}&display=PC" style="color:#D14147">切换电脑版</a></p>
  {else}
  <p><a href="{$main_path}/?display=PC" style="color:#D14147">切换电脑版</a></p>
  {/if}