From the Microsoft blog:
You will have until January 2020 to complete the transition from Internet Explorer 10 (IE10) to IE11. After this, we will not release any security or non-security updates, free or paid assisted support options, or online technical content changes for IE10.
Once IE10 and eventually IE11 die the death, it’s not clear what we’re going to be doing with all of our free time. It will feel weird only having to write code for browsers that actually adhere to web standards.