Edge is no longer a purely Microsoft product, it's now based on Chrome(Chromium) [0], or will be soon, I haven't followed this closely.
https://blogs.windows.com/windowsexperience/2018/12/06/micro...
https://blogs.windows.com/windowsexperience/2018/12/06/micro...
Edge is still wholly MS
edit:clarity
For people who have to deal with browsers for their business this is important to know what's coming in the near future.