Hello.
Firefox Desktop Browser 72 was released last week.
Firefox release schedules
Firefox release calendar
https://wiki.mozilla.org/Release_Management/Calendar
Firefox72
Mozilla provides two release notes. One is for users and the other is for developers.
Firefox 72 release note
https://www.mozilla.org/en-US/firefox/72.0/releasenotes/
Firefox 72 release note for developers
https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/72
The release note for developers lists news and changes on APIs or developer tools that may be used by web contents developers or firefox plugin developes.
You can get overview of the new release changes and prepare to manage influence on WebClass functions or your learning materials.
Pickup for webclass
I think there is nothing special to do for using WebClass with new firefox.