title: Python Selenium: click() cannot trigger event
body: <p>I try to use selenium to mimic my action on a website to convert PDF files to EXCEL files. There are three steps to complete the conversion:</p>
  
  <ol>
  <li>Upload the PDF file.</li>
  <li>Input email address.</li>
  <li>Click the 'convert' button.</li>
  </ol>
  
  <p>I wrote the code as below. However, every time I click the button the page just refreshes without actually converting the file. </p>
  
  <pre><code>from selenium  import webdriver
  import time
  
  driver = webdriver.Chrome()
  driver.get("https://pdftoexcelonline.com/en/")
  
  # Upload file
  el_upload = driver.find_element_by_name("file")
  el_upload.send_keys("/path/to/the/file")
  
  # Input email
  el_email = driver.find_element_by_name("email")
  el_email.clear()
  el_email.send_keys("&lt;email address&gt;")
  
  # Convert button
  el_button = driver.find_element_by_id("convert_now")
  el_button.click()
  time.sleep(10)
  
  driver.close()
  </code></pre>
  
  <p>This page works well when I completed the steps manually. What is reason that my code did not trigger the conversion?</p>