What it needs, and how it installs

Requirements

What it needs

• macOS 13 or later, on Apple Silicon or Intel
• Accessibility permission — this is what lets Contain move windows for you. macOS asks the first time you launch it, and Contain does nothing at all until you say yes
• Screen Recording — optional, and only if you want live thumbnails in the picker. Contain never asks for it on its own
• Nothing else — no account, no sign-up, no background helper, nothing added to your login items

You can grant or check the permission any time under System Settings → Privacy & Security → Accessibility (add Contain with + if it is not listed). Contain's own Settings tells you whether it is still in place.

Installing

Safe to install

Contain is signed and notarized by Apple, so it opens like any other app — no warning to click past, no workaround needed. Open the disk image, drag Contain to your Applications folder, and that is the whole install. It keeps itself up to date from there.

You will not find it on the Mac App Store. Apps there run walled off from the rest of the system in a way that blocks the one thing Contain does — moving another app's windows — so a store version simply would not work. We publish it directly instead, and always sign it the same way, so an update never costs you the permission you already granted.