What feature in Microsoft Edge allows users to view a summary of all open tabs?

The feature in Microsoft Edge that allows users to view a summary of all open tabs is called "Tab Groups". Here's how to use it:

1. Open Microsoft Edge on your computer.
2. Open multiple tabs that you want to group together.
3. Right-click on one of the tabs.
4. From the drop-down menu, select "Add tab to new group".
5. A colored circle will appear before the tab. Click on it.
6. A pop-up will appear where you can name the group and choose a color for it.
7. To add more tabs to the group, simply drag them to the group.

Now, you can view a summary of all open tabs in that group by clicking on the colored circle.