## 🐛 Bug Report

Running with java binding and Firefox, the framework occasionally throws NullPointerException on the isDisplayed call.

**Please see https://github.com/mozilla/geckodriver/issues/1825 for more information.** As stated from geckodriver team, the issue is apparently related to the custom JS that is executed with this method. The ticket also contains trace logs. 

## To Reproduce

Hard to provide steps, as it happens "randomly".

## Expected behavior

Should not throw exception..

## Environment

OS: Windows 10
Browser: Firefox
Browser version: 84.0.1
Browser Driver version: geckodriver 0.28.0 (c00d2b6acd3f 2020-11-03 16:29 +0200)
Language Bindings version: java 3.141.59

private String foundBy;
  protected String id;
  protected RemoteWebDriver parent;
  protected FileDetector fileDetector;
  protected void setFoundBy(SearchContext foundFrom, String locator, String term) {
    this.foundBy = String.format("[%s] -> %s: %s", foundFrom, locator, term);
  }
  public void setParent(RemoteWebDriver parent) {
    this.parent = parent;
  }
  public String getId() {
    return id;
  }
  public void setId(String id) {
    this.id = id;
  }
  public void setFileDetector(FileDetector detector) {
    fileDetector = detector;
  }
  @Override
  public void click() {
    execute(DriverCommand.CLICK_ELEMENT(id));
  }
  @Override
  public void submit() {
    execute(DriverCommand.SUBMIT_ELEMENT(id));
  }
  @Override