This is an important message for those who are still relying on IE11 in their user base.
- Moodle 3.9.x (LTS) will be the last branch actively supporting IE11. Those who really need to use IE11 longer will have to stay on Moodle 3.9.x. Note that this version will be actively maintained (security / data loss / privacy wise) until May 2023.
- Moodle 3.10.x (to be released in November 2020) will be the the first branch actively not supporting IE11. This means that all the compatibility code will be removed and IE11 will stop working in all the places where this was required.