Logging In at the Reference Desk: A 20-Minute Privacy Reset for Library PCs

The computer at the end of the reference row has been used by about forty people since it booted this morning. Most of them were doing exactly what you're about to do: check email, pay a bill, print a form, log into something that matters. None of them left a note about what they changed.

Library systems are getting better at this. Many reset the machine between sessions, some run a restore-on-reboot setup, and a few wipe the browser profile entirely. But 'many' and 'some' aren't 'all,' and you can't tell which kind of machine you're on just by looking. So the safe move is to spend twenty minutes assuming the least.

Here's the routine. It works on library desktops, hotel business centers, campus lab machines, and the shared computer at a family member's house.

Minutes 0–3: Look before you type

Before you log into anything, take stock.

Check which profile you're in. Chrome and Edge both show a little profile icon near the top right. If the name says something other than 'Guest' or a generic label, you're inside somebody's synced profile — which may mean their bookmarks, their history, and potentially their saved logins are in play. Open a fresh window from the profile menu or switch to Guest mode.

Open the extensions page. In Chrome or Edge that's chrome://extensions or edge://extensions; in Firefox it's about:addons. Scan the list. You're looking for anything you don't recognize, anything added recently, and anything with permission to 'read and change all your data on all websites.' A keylogger doesn't need to be malware-shaped — it can just be a helpful-looking toolbar extension.

Glance at the homepage and search engine. If the browser opens to a page you didn't expect, or search results route through a strange domain, stop and ask a librarian whether the machine has been reported before. Somebody may have hijacked it, and it isn't your job to fix it — it's your job not to log in on it.

Minutes 3–7: Deal with saved passwords

This is the part people skip, and it's the part that matters most.

Never let the browser save a password on a shared PC. When the 'Save password?' prompt appears after a login, click Never. Not 'Not now.' Not the X. Never.

Check what's already saved. Open the password manager page — chrome://password-manager/passwords in Chrome, about:logins in Firefox — and look at the list. If you see entries there that aren't yours, that's a sign the profile isn't being cleaned between sessions. Use Guest mode for the rest of your visit.

Kill autofill. Address and card autofill will happily populate a form for the next person. Clear any saved payment methods you find before you start, and don't add yours.

Type, don't paste, for anything sensitive. Clipboard contents can survive in a shared session, and some library machines have clipboard tools running. Typing your password is slower and safer.

Minutes 7–11: What private mode actually does

Open an incognito or private window and you get a clean cookie jar, no history in that window, and a session that vanishes when you close it. That's genuinely useful on a public machine, because it means your logins don't persist for the next person.

What it does not do is hide you from the network. The library's router still logs the connection. The sites you visit still see the library's public IP address, and so does anyone watching that network. Your employer, your school, or the library's IT department can still see where the traffic goes, even if they can't see what's inside an encrypted page.

Private mode also won't protect you from an extension that's already installed, because in most browsers extensions still run in private windows if they're allowed to. That's why the extension check comes first.

Minutes 11–15: The proxy question

This is where people get confused, so let's be plain about it.

A browser proxy routes your traffic through a server somewhere else. On a library PC, that can be genuinely useful for one narrow thing: getting past a network filter that's blocking a legitimate site you need, without installing anything on the machine. A well-run proxy configured in the browser settings — not a random extension — is a temporary tool, and it goes away when you close the window.

What a proxy does not do is make you anonymous on the library network. Your traffic still leaves the building through the same connection. All you've done is move the point where the site sees you from the library's IP to the proxy's IP. If the proxy is free and unnamed, you've also moved your traffic through a stranger's server, which is a real cost, not a theoretical one.

The rule of thumb: use a proxy to reach a blocked page, never to log into an account. If the site needs a password, do that on a connection you control.

And skip the free proxy extensions altogether. An extension that can read every page you visit is far more dangerous on a shared machine than the block it's supposedly solving.

Minutes 15–20: The exit routine

Before you stand up, run the closes.

• Log out of every site, not just close the tabs. Email, banking, social, cloud storage. Use the site's own Sign out button.
• If you signed into a browser account — Google, Microsoft, Firefox Sync — sign out of the browser itself, not just the website.
• Close all windows, including private ones, so the session actually ends.
• Clear history and cookies for the last hour if you have any doubt about the profile.
• Take anything printed with your name on it out of the tray.
• If the machine asks whether to remember you, the answer is always no.

If the system has a reboot or restart option and the librarian says it's fine, use it. A reboot clears more than a logout ever will.

After you leave the building

Once you're home, spend five more minutes. Open your account's security settings and look for active sessions — most major services list every device currently logged in. Kill anything you don't recognize. If you logged into anything sensitive on a machine you weren't sure about, change that password from your own device. It's a small inconvenience compared to the alternative.

Public computers are one of the last genuinely shared spaces left on the internet, and they're worth using. Just treat the browser like a borrowed car: check the mirrors, don't leave your keys in it, and hand it back the way you found it.