Element Web could load a malicious instance of Element Call leaking media encryption keys

Element Web is a Matrix web client built using the Matrix React SDK. Element Web, starting from version 1.11.16 up to version 1.11.96, can be configured to load Element Call from an external URL. Under certain conditions, the external page is able to get access to the media encryption keys used for an Element Call call. Version 1.11.97 fixes the problem.