Chrome Tab Merger

What it does

Chrome has no “Merge All Windows” — Safari does, Chrome only offers a per-tab Move Tab to Another Window context menu. When your tabs are strewn across half a dozen windows on three monitors, this collapses them into one window in a single keystroke, after showing you exactly what it’s about to do.

The window it merges into is the one physically nearest the centre of your display arrangement.

Why it’s an extension and not a menu-bar app

Chrome’s AppleScript dictionary gives the tab class only close, reload, execute and friends — there is no move. An external macOS app therefore can’t move a tab at all; it can only read the URL, open a new tab elsewhere, and close the original. That silently destroys back/forward history, scroll position and half-typed form input, unpins pinned tabs, dissolves tab groups, and forces every tab to reload at once.

chrome.tabs.move() relocates the live tab, and that’s only reachable from inside the browser. So: extension.

Install

git clone https://github.com/kyle-lesinger/chrome-tab-merger

Then chrome://extensions → Developer mode → Load unpacked → pick the folder. Pin the toolbar button, and confirm the ⌘⇧K shortcut at chrome://extensions/shortcuts — Chrome ignores a suggested shortcut until it has been seen on that page. Repeat per Chrome profile.

When to reach for it

• Multi-monitor setups where windows accumulate on displays you aren’t looking at.
• Before screen-sharing, when you want one tidy window instead of nine.
• Any time you’d otherwise drag tabs between windows one at a time.

Notable detail

It asks for only tabGroups and system.display — deliberately not the tabs permission, which moving tabs doesn’t require. The practical consequence is that the extension cannot read the URL or title of any tab; it counts and moves them blind.