Improving IE Driver Use with Invalid Protected Mode Settings

Users using the IE driver when they do not have the ability to properly set the Protected Mode settings of the driver, usually restricted by an overzealous IT department, have always faced challenges when using the IE driver. This has been a known issue ever since the rewritten driver was introduced in 2011. The technical reasons for requiring the setting of Protected Mode settings are well-documented, and haven’t changed in the intervening years.

In order to use the driver without setting the Protected Mode settings, the user had to resort to passing capabilities into the driver session creation, but this was still dicey because the driver could do nothing to mitigate when a Protected Mode boundary was crossed. So even then, it was possible, even likely, to receive errors like, “Unable to get current browser,” or, “Unable to find element on closed window.” As such, there was no conceivable way to work around the issue and still support all of the versions of Internet Explorer that were required. Since as of July 2019, the driver will support no versions other than IE 11, that landscape has changed somewhat. A change to the IE driver was recently (at the time of this writing) committed that makes the attempt to at least make the experience somewhat better.

Now, when the user does not set the Protected Mode settings of the browser and sends the capability to bypass the checks for those settings, the driver will attempt to predict when a Protected Mode boundary will be crossed, and set in motion a process to reattach itself to the newly created browser. This process is far from perfect. It is subject to really challenging race conditions that are truly impossible to eliminate entirely, because of the architecture of the browser itself. Nevertheless, even in its flawed state, this is still a better outcome than it was previously for users.

Please note that the advice and support policy of the IE driver will continue to be that the user must set the Protected Mode settings of the browser properly before using the driver. Any “issues” that arise by not having the settings set, but that disappear when the settings
are corrected, are not considered by the project to be valid issues. This will include, but not be limited to, issues like abandoned browser instances not being closed, use of multiple instances of the driver where the wrong browser window is connected to and automated, and issues where the driver appears to hang upon navigation to a new page. If the problem disappears when the browser is properly configured, any issue reports will be immediately closed with a note to properly configure the browser and remove the capability.

The following situations should be at least partially mitigated by the change:

  •  Navigation to a new page
  •  Clicking on a link (specifically an <a> tag) that will lead to navigation to a new page
  •  Clicking a link that opens a new window

Other cases, like navigating backward and forward through the browser history, clicking an element that submits a form, and so on, may not be handled. In those cases, issue reports will be summarily closed, unless a specific pull request fixing the issue is also provided. Additionally, use of things like proxies to capture traffic between the browser and web server may miss some traffic because of the race conditions inherent in the mechanism used to reattach to a newly created browser. Again, these race conditions are unavoidable, and
issue reports that are based on them will be immediately closed with a note indicating that the browser must have its settings properly set. These strict guidelines are not intended to be harsh, and are not put in place with the intent to avoid investigating and fixing issues;
rather, they must be enforced because the underlying architecture of the browser makes them unavoidable.

While not perfect, it’s hoped that these changes will make things a little easier for users who run against Internet Explorer, but are prevented by circumstances beyond their control from properly configuring the browser. If you’re one of those unlucky users, I hope you’ll give the driver a spin, and see how it works for you.