Comparison Summary
Comparison SummaryZen Browser avoids Google and Chromium but breaks extension support and can be buggy, while Sidekick feels dated and lacks standout features.
Only use Zen Browser if you really want a non-Chromium base, but skip Sidekick since its features and design lag behind.
Zen BrowserFirefox-based Arc Browser Spinoff
Firefox-based Arc Browser Spinoff
Sidekick BrowserAcquired and shut down by Perplexity
Acquired and shut down by Perplexity
Recommended Alternatives
Recommended Alternatives
ChatGPT AtlasBestBest AI Browser for ChatGPT users
Best AI Browser for ChatGPT users
Editor's Verdict
Editor's VerdictZen Browser at least functions as a modern browser, even if it comes with real extension limitations and some bugs from not being Chromium based. If you're coming from Chrome or Safari, you'll miss your extensions, but it still works and offers a Firefox-based Arc-like experience for people who care about that.
Sidekick isn't even an option anymore, since it was shut down and replaced by Comet Browser. There's nothing to choose or use here.
If you actually need a browser, Zen Browser is the only real choice between the two.
