As web standards evolve and technologies advance it becomes increasingly difficult to straddle the gap between legacy and modern browsers. When that gap stretches too far we must choose which side of it we want to be on. That time has come for Microsoft Internet Explorer  , and we’ve decided to let it go and continue looking to the future.
NextThought will be phasing out support for Internet Explorer in Q1 of 2020, with support ending entirely on March 31, 2020.
The downward spiral
IE usage is low and trending downward. As of December 2019 worldwide usage is 3.5% and a bit higher in the US at 5.7%. Usage was roughly double those amounts earlier in the year. Our own usage analytics reveal the same trend.
Facebook, YouTube, Twitter, and Spotify all advise users to ditch IE. Even Microsoft is telling people to stop using it. In a post titled “The perils of using Internet Explorer as your default browser,” Chris Jackson, Microsoft’s worldwide lead for cybersecurity, said everyone should stop using Internet Explorer:
“We’re not supporting new web standards for it and, while many sites work fine, developers by and large just aren’t testing for Internet Explorer these days. They’re testing on modern browsers,” said Jackson. “So, if we continued our previous approach, you would end up in a scenario where, by optimizing for the things you have, you end up not being able to use new apps as they come out. As new apps are coming out with greater frequency, what we want to help you do is avoid having to miss out on a progressively larger portion of the web!”
but y tho
We don't like telling people what browser to use. But we have finite development, testing, and support resources, and ongoing support for retired browsers consumes a disproportionate share for a dwindling number of users. It forces lowest-common-denominator solutions and workarounds, and inflates the amount of code we deploy  to all browsers, including mobile. Dropping support for IE 11 will allow us to focus on modern browsers, speed up development, increase bandwidth for new features, and ensure the browsers used by the majority of our clients, and users, work well and aren't dragged down by legacy shims in place for IE.
Flexbox (a technology that developers have been using since 2013) [...] is listed on caniuse.com as having partial support on IE due to the "large amount of bugs present."
Adding insult to injury, implementing and debugging workarounds for these issues is a thoroughly trying experience. Again, Ollie Williams:
IE also offers by far the worst debugging experience — with only a primitive version of DevTools. This makes fixing bugs in IE undoubtedly the most frustrating part of being a developer, and it can be massively time-consuming — taking time away from organizations trying to ship features.
What to expect
In the coming weeks we'll start notifying IE users and encouraging them to upgrade. These notifications will become increasingly naggy as we approach the cutoff date. After March 31, 2020, IE users will be shown an unsupported browser message and be unable to log in.
We will, of course, continue to support all modern browsers.
|||On the twentieth anniversary of the introduction of Internet Explorer 5 for Mac|
|||Salesforce extended opt-in support for IE 11 through December 2020.|
|||An entire open source project exists dedicated to documenting IE Flexbox bugs and their potential workarounds.|