When Microsoft released Edge, they stated that it was a universal app and that it could be serviced through the Windows store. Up until now, the company has not used this mechanism to update the browser and has instead opted to update it via Windows update.
With each major release of Windows 10, the company has added new features to the browser like extensions but these releases are, at best, occurring twice a year and more recently, only once per year. The problem is that browsers like Chrome and Firefox are updated frequently but Edge has been stuck, with only a couple of small exceptions, to major Windows releases to get new features.
At a session at Ignite lead by Fred Pullen, responsible for marketing Microsoft Edge and Internet Explorer to commercial customers, he clarified how Edge will be updated in the near future.
At about the 13-minute mark, Pullen states that Edge app, which includes navigation controls, reading view and other similar features will eventually get updated through the store but the engine of Edge will always be updated with Windows Update. The reason for the engine being updated through Windows Update is because that feature powers other universal apps and will require additionally testing to make sure the changes do not impact other parts of the operating system...