Disable Vertical Tabs Auto-expand in Microsoft Edge
Move the mouse pointer to the right edge of the expanded tab bar until the mouse pointer turns into a double arrow cursor.
Press and hold the left mouse button.
Now, while holding the left mouse button, press the Caps Lock key. The tab bar will now remain collapsed.
Available in Edge Canary 91.0.831.0+
More details: https://winaero.com/disable-vertical-...