Internet Explorer 11, the final IE version, was released in 2013. Some of the planned changes and updates to third-party modules used by AirwaySim will not offer full IE11 support anymore, and for that reason AirwaySim will stop officially supporting this browser. Several other web services have already stopped the support for this old browser.
All of the main functions and the basic system should still work normally with IE11 but some additional visual functions might have compatibility issues in the future.