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Does CSS CSS comments Work in HTML Email?
Adds explanatory notes to the code or to prevent the browser from interpreting specific parts of the style sheet
Quick Answer
Does CSS comments work in HTML email?
The CSS CSS comments property is supported in all major email clients tested. You can use it with confidence in your HTML emails.
Which Email Clients Support CSS CSS comments?
CSS support for CSS comments across email clients
| Email Client | Desktop | Mobile / Web | Notes |
|---|---|---|---|
| Gmail | ✓ Yes | ✓ Yes | — |
| Outlook (Windows) | ✓ Yes | ? | — |
| Outlook (Mac / Web) | ✓ Yes | ✓ Yes | — |
| Apple Mail | ✓ Yes | ✓ Yes | — |
| Yahoo! Mail | ✓ Yes | ~ Partial | — |
| Samsung Email | ? | ✓ Yes | — |
| Thunderbird | ✓ Yes | ? | — |
| ProtonMail | ? | ? | — |
| Fastmail | ? | ? | — |
Notes
- #1 Buggy. The first <head> in the HTML is removed, so comment needs to be in the `<style>` tag of a second `<head>` element.
- #2 Partial. `<style>` tag not supported with non-google account. Comment inside `style:` attribute works.
- #3 Partial. Comment inside `<style>` tag works. Comment inside `style` attribute strips the whole attribute.
- #4 Partial. `<style>` tag not supported. Comment inside `style:` attribute works.
- #5 Partial. Comment inside `style` attribute works.
- #6 Not supported. The entire rule is removed within a `<style> element. The entire inline `style` attribute is removed.
Frequently Asked Questions
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