Dynamics 365 IE 11 supportability

At the end of building a solution, everything was working. Then someone mentioned IE11, I felt a visceral punch.

Regardless many companies are still using IE11 due to various reasions, like supporting for legacy industry specific applications.

Supported but not recommended

The official Dynamics 365 documentation says IE 11 browser is supported but you also need to check requirements for individual apps. Unfortunately, not every app documentation specifies supported browsers and their versions. In that case, I guess we have to refer back to the documentation above.

Chris Jackson from Microsoft doesn’t recommend IE as your default browser.

Nothing Is Free

The new Microsoft Edge (6/Feb/2020) is based on Chromium and Firefox is pretty good at following modern web standards. So maintain a frontend code base to support Chrome, Edge, and Firefox is relatively straight forward.

On the other hand, IE11 is a different beast. It doesn’t support many new JS syntaxes, for example the arrow synx

aPromiseObject.then((input) => output);

If IE11 cannot find a form onload handler, changes are you have syntax incompatible with IE11 in your code base.

You also need to find (polyfills)[https://dev.to/thekashey/ie11-and-the-missing-polyfills-1cd9] for IE11 if they are available.

You will need to take into account extra test efforts too. Not only because of extra test runs for the browser, IE11 load page a LOT slow than Chrome, FF and Edge.