路径 /typecho/admin/write-post.php新增引用：

\Widget\Metas\Tag\Admin::alloc()->to($tags);

大约116行在section标签下

<p><input id="tags" name="tags" type="text" value="<?php $post->tags(',', false); ?>"
                                      class="w-100 text"/></p>

后新增：

<div id="exist-tags">
       <p style="background: #fff;border: 1px solid #D9D9D6;display: block;padding: 2px 4px;">
             <?php if ($tags->have()): ?>
             <?php while ($tags->next()): ?>
             <a id="mydiv<?php $tags->mid(); ?>" style="cursor:pointer;padding: 0px 6px;margin: 2px 0;display: inline-block;" onclick="mytag=document.getElementById('mydiv<?php $tags->mid(); ?>');mytag.style.backgroundColor='#E9E9E6';t=document.getElementById('tags').value;c=t?',':'';document.getElementById('tags').value=t+c+'<?php $tags->name(); ?>'" target="_blank" rel="noopener noreferrer" one-link-mark="yes"><?php $tags->name(); ?></a>
              <?php endwhile; ?>
        <?php endif; ?>  
          </p>
</div>

效果：