Another new feature is called "WebExtension Tab Management" and will mean that "WebExtensions can now hide tabs as well as manage the behavior of the browser when a tab is opened or closed, so you can expect to see exciting new extensions that take advantage of these features in the near future."
I can see it now malware hiding tabs and reopening tabs you've closed.
Hope this feature is very secure or at least can be disabled.
Biting the hand that feeds IT
