Tabs feature is already here for anybody to use! While Microsoft has been playing the indecisive Hamlet, two companies already offer a very low-cost tabs feature with a 30-day free trial.
My favorite is called "Groupy" and it's available from the folks at https://www.stardock.com/products/groupy. Groupy makes it easy to organize multiple applications into grouped tabs on your Windows desktop -- and/or to set it so all Word files open in a single window with tabs instead of multiple instances of Word. You can set it up to do this with files from must about any modern application. Normally $9.99, it's currently (March 14, 2020) on sale for $4.99. It works like a gem in Windows 10, 8, 8.1 and even 7. You can install one license on each of two computers.
The other is TidyTabs from https://www.nurgo-software.com/products/tidytabs. It does everything that Groupy does, just not as visually pleasing to my taste. There's a free version that lets you group 3 tabs together and the licensed version with no tab limits for $18.00 - with substantial discounts for 2 or more licenses. It's really all a matter of personal preference (and price) as to which would suit you the best. But with 30-day free trials available, you can test them both and decide.
Both applications allow you to group together different programs with tabs -- all in the same window. And they also allow you to set it up so that all files you open in a program will open in the same window with a tab for each file. Both offer considerable customization if you don't like the defaults.