QTTabBar

Discontinued, yes - but still the best with the most options by far!

In 2018 it is still the best way to get tabs on Windows Explorer. Fully customizable, clean, integrates nicely with Windows 10.

Tabs, yes, of course. But that's just a small part. You can change text color and background color of files and folders (useful so that you'll never delete something by mistake) open cmd, have groups and favorites in explorer, launch programs, close tabs to the right, to the left, all, create shortcuts for doing almost everything you can think of, capture windows, split the screen in two or three "views", change Explorer appearance, customize it to your heart's content, while, at the same time, it still being the Explorer you know and feel comfortable with.
I installed it quite a few years ago and have never felt the need to try anything else. I wouldn't know what to do without it now. First thing I install when reinstalling windows. Sure, to get the most of it you'll have to invest some time, it has so many options, but you probably don't need everything it's able to do. With just a handful of it's options, your experience with explorer will be so much better that, in a short time you won't even remember what Explorer looked like without QTTabBar.

I had no problems, however, I think the position of the tabs are hidden and I ended up forgetting that I installed this functionality. I prefer ExplorerMax which adds tabs like chrome and no bugs like Clover

Just downloaded a few hours ago, it seems very good by now. Integrates perfectly with Windows Explorer.

With some setting tweaking it becomes very responsive and quite useful in many situation, with it's built in previewer and all.
Default settings suck though. Works on latest Windows 10.

Bestows the powers of a mystical Ninja Pirate!