cf273ec6 removed ie11 as a target. A side effect is that this also removed support for Safari 12, which we will be maintaining support for until January 2023 https://meta.discourse.org/t/224747
cf273ec6
## Ember Upgrade Context: https://deprecations.emberjs.com/v3.x/#toc_3-0-browser-support-policy
These changes should all be safe to live in master even if they're not being used yet.