--- a/testing/marionette/driver.js
+++ b/testing/marionette/driver.js
@@ -3142,17 +3142,17 @@ GeckoDriver.prototype.maximizeWindow = a
  *
  * @throws {UnsupportedOperationError}
  *     Not available for current application.
  * @throws {NoSuchWindowError}
  *     Top-level browsing context has been discarded.
  * @throws {UnexpectedAlertOpenError}
  *     A modal dialog is open, blocking this operation.
  */
-GeckoDriver.prototype.fullscreen = async function(cmd, resp) {
+GeckoDriver.prototype.fullscreenWindow = async function(cmd, resp) {
   assert.firefox();
   const win = assert.window(this.getCurrentWindow());
   assert.noUserPrompt(this.dialog);
 
   await new Promise(resolve => {
     win.addEventListener("sizemodechange", resolve, {once: true});
     win.fullScreen = !win.fullScreen;
   });
@@ -3588,17 +3588,17 @@ GeckoDriver.prototype.commands = {
   "WebDriver:ElementClear": GeckoDriver.prototype.clearElement,
   "WebDriver:ElementClick": GeckoDriver.prototype.clickElement,
   "WebDriver:ElementSendKeys": GeckoDriver.prototype.sendKeysToElement,
   "WebDriver:ExecuteAsyncScript": GeckoDriver.prototype.executeAsyncScript,
   "WebDriver:ExecuteScript": GeckoDriver.prototype.executeScript,
   "WebDriver:FindElement": GeckoDriver.prototype.findElement,
   "WebDriver:FindElements": GeckoDriver.prototype.findElements,
   "WebDriver:Forward": GeckoDriver.prototype.goForward,
-  "WebDriver:FullscreenWindow": GeckoDriver.prototype.fullscreen,
+  "WebDriver:FullscreenWindow": GeckoDriver.prototype.fullscreenWindow,
   "WebDriver:GetActiveElement": GeckoDriver.prototype.getActiveElement,
   "WebDriver:GetActiveFrame": GeckoDriver.prototype.getActiveFrame,
   "WebDriver:GetAlertText": GeckoDriver.prototype.getTextFromDialog,
   "WebDriver:GetCapabilities": GeckoDriver.prototype.getSessionCapabilities,
   "WebDriver:GetChromeWindowHandle": GeckoDriver.prototype.getChromeWindowHandle,
   "WebDriver:GetChromeWindowHandles": GeckoDriver.prototype.getChromeWindowHandles,
   "WebDriver:GetCookies": GeckoDriver.prototype.getCookies,
   "WebDriver:GetCurrentChromeWindowHandle": GeckoDriver.prototype.getChromeWindowHandle,
@@ -3648,17 +3648,17 @@ GeckoDriver.prototype.commands = {
   "deleteAllCookies": GeckoDriver.prototype.deleteAllCookies,
   "deleteCookie": GeckoDriver.prototype.deleteCookie,
   "deleteSession": GeckoDriver.prototype.deleteSession,
   "dismissDialog": GeckoDriver.prototype.dismissDialog,
   "executeAsyncScript": GeckoDriver.prototype.executeAsyncScript,
   "executeScript": GeckoDriver.prototype.executeScript,
   "findElement": GeckoDriver.prototype.findElement,
   "findElements": GeckoDriver.prototype.findElements,
-  "fullscreen": GeckoDriver.prototype.fullscreen,
+  "fullscreen": GeckoDriver.prototype.fullscreenWindow,
   "getActiveElement": GeckoDriver.prototype.getActiveElement,
   "getActiveFrame": GeckoDriver.prototype.getActiveFrame,
   "getChromeWindowHandle": GeckoDriver.prototype.getChromeWindowHandle,
   "getChromeWindowHandles": GeckoDriver.prototype.getChromeWindowHandles,
   "getCookies": GeckoDriver.prototype.getCookies,
   "getCurrentChromeWindowHandle": GeckoDriver.prototype.getChromeWindowHandle,
   "getCurrentUrl": GeckoDriver.prototype.getCurrentUrl,
   "getElementAttribute": GeckoDriver.prototype.getElementAttribute,