:grouping
selector or pseudo-class · 12 supported, 2 partial, 0 unsupported across 15 clients
Selector grouping (a, b, c) applies the same styles to multiple selectors at once. It is a CSS authoring convenience rather than a behavior — when <style> blocks are preserved, grouped selectors behave identically to writing them separately. Outlook strips <style>, so grouped selectors are inert there.
Client Support
| Client | Category | Engine | Support |
|---|---|---|---|
| Gmail | webmail | Gmail Web | Supported |
| Gmail Android | mobile | Gmail Mobile | Partial |
| Gmail iOS | mobile | Gmail Mobile | Partial |
| Outlook 365 | webmail | Outlook Web | Supported |
| Outlook (New) | desktop | Outlook Web | Supported |
| Outlook Classic | desktop | Microsoft Word | Supported |
| Outlook iOS | mobile | Outlook Mobile | Supported |
| Outlook Android | mobile | Outlook Mobile | Supported |
| Apple Mail | desktop | WebKit | Supported |
| Apple Mail iOS | mobile | WebKit | Supported |
| Yahoo Mail | webmail | Yahoo | Supported |
| Samsung Mail | mobile | Samsung | Supported |
| Thunderbird | desktop | Gecko | Supported |
| HEY Mail | webmail | WebKit | Supported |
| Superhuman | desktop | Blink | Unknown |
Client-by-client behaviour for :grouping
Fully supports :grouping (12): Gmail, Outlook 365, Outlook (New), Outlook Classic, Outlook iOS, Outlook Android, Apple Mail, Apple Mail iOS, Yahoo Mail, Samsung Mail, Thunderbird, HEY Mail.
Partial support (2): Gmail Android, Gmail iOS. Expect rendering quirks unique to each engine — partial support typically means a subset of values, an ignored shorthand, or sanitizer-specific rewrites.
Behaviour unverified in: Superhuman.
When to use :grouping in email
- Applying a single base font-family rule to all text-bearing elements at once.
- Resetting margin on multiple heading levels with one rule.
- Sharing dark-mode color overrides across several distinct elements.
Rendering behaviour and edge cases
- Grouping is purely syntactic — supported wherever each individual selector is supported.
- Outlook ignores all <style>-based grouping.
- Long groups can become hard to maintain — keep groups focused on a single styling concern.
Recommended fallback strategy
Use selector grouping freely in <style> blocks for cleanliness. For Outlook coverage, duplicate the grouped styles inline on each affected element.
Fixes & Workarounds
Gmail Android
Partial":grouping" is not supported in this email client.
Gmail iOS
Partial":grouping" is not supported in this email client.
Related Features
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Try Emailens FreeSupport data last updated Apr 27, 2026 · synced from caniemail.com via @emailens/engine.