We've known for a while that the Chrome team was working on tab groups. The feature first showed up in Canary on the desktop, but it's now made its way to Android, also in the Canary channel. It's hidden behind a flag though, and works... sort of.
The "Tag groups" flag (found at the URL chrome://flags/#enable-tab-groups) lets you enable groups. The only way to trigger them now is to open a new tab and tap and hold on any icon in the recommended sites. You'll see the "Open in new tab in group" option. A new bottom menu (which is the weird interface we covered a while back) will appear, and this is where the tabs belonging to this group reside. You can switch between them, open a new tab, and expand the menu to view tab thumbnails and close them.
Left: Opening in a new tab group. Right: Switching between tabs in a group.
The feature is still unfinished though. When you access the regular tab switcher, the group is only represented by the last tab you viewed in it. There's no stack of cards, for example, to show that this is a group, which can get very confusing.
Another issue I came across is that the flag to activate it is really flakey. Yesterday, it wasn't triggering the behavior at all, today it started force closing Chrome until I cleared all data and started again, and now it's finally working. So if you want to test this out, keep in mind that it's not reliable. But then again, this is Canary so you should be prepared for it.
With the latest Chrome Canary v75.0.3748 (APK Mirror), tab groups have received a couple of improvements. First, there's a new button to create a group in the grid tab layout. So instead of having to go through a link on the home page to do it, you can now easily start a group from the switcher. Second is that a tab group is represented by a grid of mini thumbnails, and the number of tabs inside is clear.
Left: Create group from the tab switcher. Right: Tab groups show mini thumbnails now.
Finally, one last improvement was discovered by our tipster, Nick Cipriani. You can now swipe any of the tabs or groups away (left to right) in the switcher. This feature was missing when the grid layout was introduced. Tapping the small close button was certainly more annoying than a simple swipe.
Now in Stable
Just like the grid tab layout, this new tab grouping feature has trickled down from Canary to Dev, Beta, and is showing up for some users on Chrome Stable v74. If you don't have it but would still like to try it out, the flag is also available so you can manually enable it.
A new flag has popped up in Chrome (currently on both Dev v76 and Canary v76, but not on Beta v75 or Stable v74) for tab group UI improvements. You can enable it at chrome://flags/#enable-tab-groups-ui-improvements. Restart your browser twice, and you'll notice one welcome change in the way tab groups are handled. When tapping on a group from the tab switcher, you now get a large pop-up with thumbnails of all the included tabs, letting you choose which one to jump to immediately. If the flag is set to default or disabled, tapping on the group opens the last viewed tab in it, without giving you the choice beforehand.
Left: Tab groups UI improvements flag. Right: Pop-up to choose which tab to go to in a group.