title: First character is missing inconstantly while sending string to the ExtJS input via sendKeys()
body: <p>I randomly face the issue of missing first character in the ExtJS5 input field, while sending string via sendKeys method.</p>
  
  <p>System info:
  Ubuntu 14.04 -> docker containers with selenium grid (2.48.2)
  Browser Firefox </p>
  
  <p>Code is simple. I just get input web element, wait if it's clickable (i.e. isEnabled and isDisplayed), clear and send string:</p>
  
  <pre><code>wait.until(ExpectedConditions.elementToBeClickable(input)).clear();
  input.sendKeys(value);
  </code></pre>
  
  <p>input element is simple too:</p>
  
  <pre><code>&lt;input id="textfield-1455-inputEl" data-ref="inputEl" type="text" role="textbox" size="1" name="name" class="x-form-field x-form-required-field x-form-text x-form-text-default x-form-focus x-field-form-focus x-field-default-form-focus" autocomplete="off" componentid="textfield-1455"/&gt;
  </code></pre>
  
  <p>I've noticed that issue occurs only for the first sendKeys() executing on the page: </p>
  
  <ul>
  <li>Enter the page, wait for page load, work with first input</li>
  <li>Enter the page, wait for page load, choose Enable into corresponding select box in order to enable input field, work with input field (<a href="https://i.stack.imgur.com/qrNKQ.png" rel="nofollow noreferrer">image with this example is attached</a>)</li>
  <li>Enter the page, wait for page load, click button add in order to add the needed input field, work with input field</li>
  </ul>
  
  <p>Other occurrences of the sendKeys on the page are stable.</p>
  
  <p>I've looked for similar questions. It does not seem the issue with special characters (Missing characters example: 46-> 6; coverTest -> overTest; 1 -> nothing);</p>
  
  <p>Also, I don't think it's an issue with missing characters due to remote webdriver infrastructure. The tests fail randomly but in exact places.</p>
  
  <p>I know that I can use sendKeys(), then check the value of the input and repeat the sending action. However, it's the last option.</p>
  
  <p>Is there any additional check needed for ExtJS input (any attribute in DOM) in order to be sure that input field is ready? </p>
  
  <p>Appreciate your help. </p>