What we found
Google Chrome: FChrome tags you with a permanent ID on install.
Chrome assigns a unique client ID on installation that persists across sessions and is sent to Google with every sync, crash report, and usage metric. Combined with Google account sign-in (prompted aggressively), this creates a permanent identity linking all your browsing to your real name, email, and Google advertising profile.
Microsoft Edge: FAcademic research proved Edge is the least private browser you can use — worse than Chrome.
Trinity College Dublin research ranked Edge as the LEAST PRIVATE major browser — worse than Chrome, Firefox, Safari, and Brave. Edge sends a persistent hardware UUID to Microsoft that cannot be disabled or reset. It phones home on first launch before any user consent. It was ranked alongside Yandex (Russian) in the worst privacy tier.
Opera Browser: FOpera looks Norwegian.
Opera was acquired by a Chinese consortium led by Kunlun Tech (Beijing) for $1.2 billion in 2016. The company is now headquartered in Norway but controlled from Beijing. Opera's "free VPN" routes traffic through servers operated by a Chinese-owned company. Users trust a browser owned by a Chinese company subject to China's National Intelligence Law with all their browsing data.
Apple Safari: DSafari sends every URL you visit to Google for 'safe browsing' checks.
Safari sends URLs to Google Safe Browsing for phishing checks — and in China, to Tencent Safe Browsing. Apple didn't clearly disclose the Tencent data sharing until researchers discovered it in 2019. Your 'private' browser is sending your browsing data to Google and, if you're in China, to a company subject to China's National Intelligence Law.
Brave Browser: DThe 'privacy browser' was caught secretly adding its own referral codes to crypto exchange URLs.
In June 2020, Brave was caught injecting affiliate referral codes into cryptocurrency URLs — adding Brave's referral link to Binance, Coinbase, Ledger, and Trezor URLs. Users typing a crypto exchange URL got silently redirected through Brave's affiliate link, earning Brave commission. CEO Brendan Eich apologised and called it 'a mistake' but the code was intentional.
Arc Browser: DArc built a cult following.
In October 2024, The Browser Company announced it was pivoting away from Arc to build a new product called "Dia" — an AI-native browser. CEO Josh Miller said Arc was "too complex for the average user." Existing Arc users were told the browser would continue to receive security updates but no major new features. A browser with a passionate community was effectively sunset to chase AI hype. Users who built their workflow around Arc's unique features (Spaces, Boosts, sidebar tabs) were abandoned mid-relationship.