:focus
selector or pseudo-class · 11 supported, 1 partial, 8 unsupported across 21 clients
11 of 21 email clients render :focus fully (Sep 2, 2026 data); it breaks outright in Gmail, Gmail Android, Gmail iOS and 5 more.
- 4/7 webmail, 3/6 desktop, 4/8 mobile clients support :focus fully.
- Unsupported in Gmail, Gmail Android, Gmail iOS, Outlook (New) and 4 more.
- Partial in Outlook 365, behavior differs from browsers, test before relying on it.
- Outlook Classic (Word engine, supported to at least 2029) does not fully support :focus, and its replacement changes little here; see the deprecation diff.
- Across all clients, only 6 of 298 tracked HTML/CSS features render identically everywhere.
Source: caniemail.com (MIT), via the Emailens engine. Last tested upstream Oct 28, 2019, synced by Emailens Sep 2, 2026.
Client Support
| Client | Category | Engine | Support |
|---|---|---|---|
| Gmail | webmail | Gmail Web | Unsupported |
| Gmail Android | mobile | Gmail Mobile | Unsupported |
| Gmail iOS | mobile | Gmail Mobile | Unsupported |
| Outlook 365 | webmail | Outlook Web | PartialSee caveat 1 |
| Outlook (New) | desktop | Outlook Web | Unsupported |
| Outlook Classic | desktop | Microsoft Word | Unsupported |
| Outlook iOS | mobile | Outlook Mobile | Unsupported |
| Outlook Android | mobile | Outlook Mobile | Supported |
| Outlook for Mac | desktop | WebKit | Supported |
| Apple Mail | desktop | WebKit | Supported |
| Apple Mail iOS | mobile | WebKit | Unsupported |
| Yahoo Mail | webmail | Yahoo | Supported |
| Yahoo Mail Android | mobile | Yahoo | Supported |
| Yahoo Mail iOS | mobile | Yahoo | Supported |
| Samsung Mail | mobile | Samsung | Supported |
| Thunderbird | desktop | Gecko | Supported |
| HEY Mail | webmail | WebKit | Supported |
| Proton Mail | webmail | Proton | Supported |
| AOL Mail | webmail | AOL | Unsupported |
| Fastmail | webmail | Fastmail | Supported |
| Superhuman | desktop | Blink | Unknown |
Documented caveats (1)
- 1.Outlook 365: Partial. Only supported on type selectors.
Caveats recorded by caniemail.com (MIT) and carried verbatim, one entry per wording rather than per client.
Client-by-client behaviour for :focus
Fully supports :focus (11): Outlook Android, Outlook for Mac, Apple Mail, Yahoo Mail, Yahoo Mail Android, Yahoo Mail iOS, Samsung Mail, Thunderbird, HEY Mail, Proton Mail, Fastmail.
Partial support (1): Outlook 365. Expect rendering quirks unique to each engine. Partial support typically means a subset of values, an ignored shorthand, or sanitizer-specific rewrites.
No support (8): Gmail, Gmail Android, Gmail iOS, Outlook (New), Outlook Classic, Outlook iOS, Apple Mail iOS, AOL Mail. Plan fallbacks for these clients before relying on :focus in production sends.
Behaviour unverified in: Superhuman.
Fixes & Workarounds
Gmail
Unsupported":focus" is not supported in this email client.
Gmail Android
Unsupported":focus" is not supported in this email client.
Gmail iOS
Unsupported":focus" is not supported in this email client.
Outlook (New)
Unsupported":focus" is not supported in this email client.
Outlook Classic
Unsupported":focus" is not supported in this email client.
Outlook iOS
Unsupported":focus" is not supported in this email client.
Apple Mail iOS
Unsupported":focus" is not supported in this email client.
AOL Mail
Unsupported":focus" is not supported in this email client.
Outlook 365
Partial":focus" is not supported in this email client.
Related Features
Check your own HTML for :focus
Paste your own, or run the sample below. Analyzed in this page, with no signup and nothing stored.
Test your :focus layout across 21 email clients
Preview rendering, catch CSS issues, and see how :focus displays across Outlook, Gmail, and Apple Mail. Free, no account needed.
Instant live preview · No signup required · 21 email engines
Last tested upstream: · Last synced by Emailens:
caniemail.com (MIT) records Oct 28, 2019 as the last time :focus was tested in a real client, 6 years before this sync. Syncing copies that result forward, it does not re-test it. Carried in @emailens/engine data v0.12.2.