Pseudo-element · data last changed 10 Nov 2026
::after in email clients
Works in 6 of 21. Not supported in Gmail, Gmail Android, Gmail iOS and 7 more. Partial in Outlook 365, Outlook (New), Outlook iOS and 1 more. Untested in Superhuman.
Your reader in Outlook Classic sees the email without ::after, even if it looks right where you tested it.
caniemail (MIT) via @emailens/engine 0.18.22
What to do instead in Outlook Classic
Include trailing arrows and decorative characters directly in your HTML anchor text (e.g., <a href="...">Read guide →</a>). For decorative divider lines, use standard <td> borders or height: 1px divider tables rather than ::after pseudo-elements.
There is no drop-in fix for ::after in Outlook Classic. Design so the email still reads without it.
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::after is not among the 24 features we have screenshotted on real installs. The ones we have →
All 21 clients, problems first
| Client | Support |
|---|---|
| Gmail | Not supported |
| Gmail Android | Not supported |
| Gmail iOS | Not supported |
| Outlook Classic | Not supported |
| Outlook Android | Not supported |
| Yahoo Mail | Not supported |
| Yahoo Mail Android | Not supported |
| Yahoo Mail iOS | Not supported |
| Proton Mail | Not supported |
| AOL Mail | Not supported |
| Outlook 365 | Partial See caveat 1 |
| Outlook (New) | Partial See caveat 1 |
| Outlook iOS | Partial See caveat 1 |
| Outlook for Mac | Partial See caveat 2 |
| Superhuman | Untested |
Works in 6: Apple Mail, Apple Mail iOS, Samsung Mail and 3 more. Show all
| Client | Support |
|---|---|
| Apple Mail | Works |
| Apple Mail iOS | Works |
| Samsung Mail | Works |
| Thunderbird | Works |
| HEY Mail | Works |
| Fastmail | Works |
Caveats (2)
- 1. Outlook 365, Outlook (New), Outlook iOS: Partial. Only supported on type selectors.
- 2. Outlook for Mac: Not supported with non Outlook accounts. Partial. Only supported on type selectors.
Caveats as recorded by caniemail (MIT), one entry per wording.
How ::after behaves
The CSS ::after pseudo-element inserts generated content immediately after an element's content. Similar to ::before, designers often attempt to use it for trailing arrows, link indicators, or clearfix hacks, but it is stripped across the vast majority of email clients.
- Gmail strips ::after declarations entirely from <style> blocks during message sanitization.
- Outlook Classic does not support CSS pseudo-elements and ignores ::after completely.
- Outlook 365 and Outlook iOS offer partial support: they honor ::after on type selectors (e.g., a::after), but strip it on class selectors.
- Apple Mail and Thunderbird support ::after, executing the content property and accompanying styles.
Questions
Can I use ::after for a clearfix in email?
No. Clearfix via ::after fails in Outlook and Gmail. Use table-based column layouts (<td>) instead of floated divs, completely eliminating the need for clearfixes.
Does Outlook (New) support ::after?
Yes, Outlook (New) supports ::after, but Outlook Classic does not, so real HTML markup remains necessary for desktop reach.
Your next question
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