code: public Actions sendKeys(CharSequence... keys) {
      if (isBuildingActions()) {
        action.addAction(new SendKeysAction(jsonKeyboard, jsonMouse, null, keys));
      }
  
      return sendKeysInTicks(keys);
    }
docs: Sends keys to the active element. This differs from calling
  {@link WebElement#sendKeys(CharSequence...)} on the active element in two ways:
  <ul>
  <li>The modifier keys included in this call are not released.</li>
  <li>There is no attempt to re-focus the element - so sendKeys(Keys.TAB) for switching
  elements should work. </li>
  </ul>
  
  @see WebElement#sendKeys(CharSequence...)
  
  @param keys The keys.
  @return A self reference.
  
  @throws IllegalArgumentException if keys is null