One thing that will not be in the November update for Windows 10 is extensions for Microsoft Edge. The browser should be updated in general, that feature needs a little more time before it is ready for the public. The official statement has the feature arriving in “a future Windows 10 update in 2016”. We still don't know how frequent these updates will occur, but Mary Jo Foley has sources that say “Redstone 1” will be released in June (give or take maybe?).
Microsoft also has not elaborated too much on what this extension model will be. The Ars Technica source reports that Microsoft will allow add-ons to be written in “HTML-plus-JavaScript” but they do not elaborate on whether privileged APIs will be available, and what those would be. Whatever is being planned, Microsoft has been dead-silent about it.
To me, this means that it's either far off, or completely mundane.
