Cookie Authentication

Some videos aren't available to everyone — they might be private, age-restricted, or require a membership. To download these, Fetchii needs to prove you have permission to view them. That's where cookies come in.

How It Works

When you log into a website like YouTube, your browser stores small pieces of data called cookies. These cookies tell the website who you are so you don't have to log in every time you visit.

Fetchii can use these same cookies to download videos on your behalf. It's like lending the website your ID card temporarily — Fetchii shows your cookies, the website confirms you have access, and the download proceeds.

The Easy Way: Browser Extensions

The simplest approach is to use the browser extension's right-click menu:

1. Log into the website in your browser as usual
2. Right-click on a video or link you want to download
3. Select "Download with Fetchii" from the context menu
4. The extension sends the URL and your cookies to Fetchii together

That's it. Your cookies are sent along with each download request — no manual exporting needed.

This works with YouTube (including Premium), Vimeo, X, Instagram, Facebook, and most other sites that require login.

When a Download Needs You to Sign In

If a download you started in Fetchii fails because the site wants you signed in, its row shows a Resolve… button. Click it to open the sign-in sheet:

• Use Browser Extension (Recommended) — make sure you're logged into the site in your browser, then click Retry with Extension, or Open in Browser to open the page there first. If the extension isn't installed yet, this card says Install Browser Extension instead and offers Set up browser extension.
• Auto Import from Browser (Alternative) — next to Quick retry with browser cookies:, click Firefox or Google Chrome to retry with that browser's cookies right away. This also sets the browser as your Use sign-in from choice (see below).

What You Can Download

With your cookies, Fetchii can access:

• Private videos — Videos you've set to "private" on your own channel
• Unlisted videos — Videos shared only via direct link
• Age-restricted content — Videos that require login to verify your age
• Member-only videos — Channel membership exclusives
• Subscription content — Videos from paid services you subscribe to

If you can watch it in your browser while logged in, Fetchii can usually download it.

Alternative: Browser Cookie Settings

If you prefer not to use browser extensions, you can configure Fetchii to read cookies directly from your browser's local data.

Go to Settings > Advanced and find the Signed-In Sites section. Use the Use sign-in from menu to pick your browser (the menu lists the supported browsers installed on your Mac):

• Firefox (Recommended) — Works immediately without any extra permissions
• Google Chrome, Brave, Microsoft Edge, Chromium — Require Keychain access permission (you'll be prompted to allow this)

Safari isn't offered here — for Safari, use the extension.

When this is configured, Fetchii will automatically read your logged-in sessions from the selected browser whenever you download from a site that requires authentication. If macOS blocks Fetchii from reading the browser's data, a notice appears in the bar under the toolbar, with an Open System Settings button.

Note: This reads your existing browser cookies — you still need to log into websites through your browser first.

Security and Privacy

You might wonder: are my login cookies safe with Fetchii?

Stored locally — Your cookies never leave your Mac. They're saved in Fetchii's local data folder, not uploaded anywhere.

Encrypted storage — Cookies are encrypted when stored, so other apps can't read them.

Used only for downloads — Fetchii only sends cookies to the original website when downloading. They're never shared with third parties.

Cookies the extension sends are kept for the period set in Settings > Browser Extension > Cookies from Browser Extension > Cookie retention (7 days by default). To remove them sooner, look at Stored browser cookies in the same section: click the trash button next to a site, or Clear All Cookies to remove everything. Alternatively, delete the cookies folder directly at:

~/Library/Application Support/Fetchii/cookies/

When Things Don't Work

"Login Required" error: The cookies might have expired or the website logged you out. Log back into the site in your browser, then download again with the extension, or click Resolve… on the failed download and choose Retry with Extension.

Cookies expiring quickly: Some sites issue short-lived cookies. If downloads fail after a few hours, just send the download again from your browser so the extension passes fresh cookies.

Two-factor authentication sites: After completing 2FA in your browser, download again with the extension. The cookies should work until you explicitly log out.

Best Practices

Keep these tips in mind for smooth cookie-based downloads:

• Stay logged in — Keep the site logged in on your browser so cookies remain valid
• Download again after password changes — New password means new cookies
• Use the extension when possible — It's easier and always gives you fresh cookies
• Don't share cookie files — They contain your login session and could let someone access your account