Safari 15, which is already available for macOS Catalina and Big Sur, will be part of macOS Monterey too. One of the design changes to the updated browser is the separation of tab indicators from its web content. Apple has inexplicably interposed the Favorites bar in between the two, and even if you hide the bar, figuring out which tab is the active one can be difficult.

ActiveTab is a new Safari extension inspired by The Tragedy of Safari 15 for Mac’s ‘Tabs’ a story John Gruber wrote on Daring Fireball recently that you should read if you haven’t already. To make it easier to distinguish the active tab, ActiveTab draws a line underneath it along the top of the tab’s web content. There are eight colors to choose from, and the line can be anywhere from 1 to 7 pixels wide. Note that a page needs to be open for the line to appear because it’s being drawn on top of the content. As a result, you won’t see the line if a tab is empty.

I wish ActiveTab offered different colors for light and dark mode browsing.

The extension, which Stephen Hackett shared with me earlier today, undeniably makes it easier to spot the active tab in Safari. However, I found myself wishing almost immediately for light and dark mode versions of the color options that could switch between light and dark mode in sync with my system settings because the colors don’t all work equally well in both modes. The colors of the site you visit can affect the visibility of ActiveTab’s indicator too.

Of course, I’d prefer if Apple fixed the design of its tabs, but if you find yourself being tripped up by the new design, ActiveTab is worth considering.

ActiveTab is available on the Mac App Store for $1.99.