title: Unable to use 'x' and '+' markers in Seaborn stripplot
body: <p>I am trying to use seaborn.stripplot() to do categorical plots as shown below  using the reproducible code:</p>
  <pre><code>import seaborn as sns
  
  df = sns.load_dataset('iris')
  
  sns.stripplot(data = df,
                x=&quot;species&quot;, y=&quot;sepal_length&quot;, 
                color = 'red',jitter=False,zorder=3, marker='X')
  </code></pre>
  <p><a href="https://i.stack.imgur.com/jiRkM.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jiRkM.jpg" alt="enter image description here" /></a></p>
  <p>But when I use <code>'x'</code> or <code>'+'</code> or <code>'_'</code> and other non-filled markers as a marker it is returning nothing, why so?</p>