title: Web-scraping with rvest works with first page of website, but not others
body: <p>Here is the code I'm using to get the link to the next page of the website.</p>
  
  <pre><code>url &lt;- 'https://uws-community.symplicity.com/index.php?s=student_group'
  webpage &lt;- read_html(url)
  next_link &lt;- html_nodes(webpage,".paging_nav a") %&gt;% html_attr('href')
  </code></pre>
  
  <p>Then, using that link, I'm trying to get the next page after that.</p>
  
  <pre><code>url2 &lt;- paste0("https://uws-community.symplicity.com/index.php", 
  next_link)
  
  webpage2 &lt;- read_html(url2)
  next_link2 &lt;- html_nodes(webpage2,".paging_nav a") %&gt;% html_attr('href')
  </code></pre>
  
  <p>This second part gives me "Character (empty)" for next_link2. Why is this? Why did the same method work on the first page but not on the second page?</p>