When you sign in to a site in the Mac app's browser windows, that login is saved to your browser automatically.
Your agents can then use it in future chats — on the web or Mac, in any workspace — without signing in again. The sync happens in the background once the sign-in settles.
Where: Mac app. Synced logins appear in Plugins › Your browser under My browser.
Good to know: browser login sync applies to Hermes, Claude Code, and Codex. Google logins aren't copied between your Mac and the cloud: Google refuses a sign-in moved into another browser, so sign in to Google directly where the agent runs. Claude Code and Codex chats that run on your Mac use the Mac app's browser with your Mac sign-ins, unless the chat is set to Signed out, uses a browser someone shared with you, or is shared; then they start signed out. Logins from your Mac are yours; teammates can use them only if you share your browser with them. A Chrome tab you lend with Use this Chrome tab is never used for login sync; its sign-ins stay in Chrome (Let an agent act in your own Chrome tab). Related: Share your browser logins, Manage saved browser logins.