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Two Simple UX Changes That Could Make Phishing Harder

Phishing works because browsers present URLs in the worst possible way. The default sans-serif font makes lookalike characters identical, nothing separates the domain from the noise around it, and non-Latin characters that resemble Latin letters blend right in.

Two small changes could fix most of this:

  1. Highlight the domain so your eye is drawn to the part that actually matters.
  2. Use a distinguishable font — and flag non-Latin characters that could be mistaken for Latin ones.

Neither removes information. Neither requires user education.

The Proposal

Compare a standard address bar with a safer version:

Standard address bar
Legitimate
https://www.paypal.com/signin
Phishing — capital I instead of l
https://www.paypaI.com/signin
Phishing — Cyrillic а, р
https://www.раypal.com/signin
Safe address bar
Legitimate
https://www.paypal.com/signin
Phishing — capital I instead of l
https://www.paypaI.com/signin
Phishing — Cyrillic а, р flagged
https://www.раypal.com/signin

The standard bar makes all three URLs look nearly identical. The safe bar uses a monospace font (making the I/l difference visible), highlights the domain, and flags non-Latin characters with a dotted underline — the Cyrillic р and а look identical to Latin p and a but are different Unicode codepoints.

The same idea works for email, where phishing is arguably worse because clients hide the real address behind a display name:

Standard email client
Legitimate
noreply@amazon.com
Phishing — rn instead of m
noreply@arnazon.com
Safe email client
Legitimate
noreply@amazon.com
Phishing — rn instead of m
noreply@arnazon.com

The rn → m trick: arnazon looks like "amazon" in most sans-serif fonts. A distinguishable font keeps the characters visually separate.

Domain Highlighting

Give the registrable domain (the eTLD+1) a subtle background highlight. Firefox already grays out everything except the domain — a proper highlight goes further by actively drawing the eye rather than just dimming the surroundings.

A Distinguishable Font

Switch to a font where I/l/1 and O/0 are unmistakable, and where rn doesn’t collapse into m. Fonts like JetBrains Mono, IBM Plex Mono, or Fira Code are built for exactly this.

Non-Latin Character Flagging

Homograph attacks use characters from other scripts that look identical to Latin letters — Cyrillic а, е, о, р, с, х or Greek ο, α are visually indistinguishable from their Latin counterparts in most fonts. A safe address bar should flag any non-Latin characters in an otherwise Latin-looking domain — for example with a dotted underline or different background. Browsers already have IDN homograph detection; it just needs a visual treatment.

Why This Could Ship

Google tried twice (2014, 2020) to improve URL display by hiding parts of the URL. Both times they abandoned it — users hated it, and it didn’t improve security metrics. The lesson: don’t subtract information, add signal.

These changes are the opposite — low-risk, low-effort, and additive. It’s a font change and a highlight on one UI element. Both Firefox and Chrome already have the eTLD parsing logic. This is a UI tweak, not an architectural change.


Small changes. Won’t stop all phishing. But they make the address bar work with your visual system instead of against it.

This post was written with AI assistance and reviewed by humans.