Activation · Studio
Overall compatibility: 96/100 across 21 email clients · 20 of 21 clients passing (7 clean at 100%) · 121 compatibility warnings (0 error-level) · 12.8KB compiled HTML.
Attribution · React Email
Template adapted from the open-source React Email collection under the MIT License (© Plus Five Five, Inc. / Resend). Full React source code is included.
Client Compatibility
Score: 96/100 · 20/21 passing
Notes on this template
It opens: "One last step Thanks for creating your Halo account. To shop, track ring orders, and get updates, please confirm this email address. Confirm Email Halo is the AI ring on your finger, easy shopping, clear shipping, and real support when...". Preheader: "Confirm your email address". 5 images, 2 Outlook-only blocks, no dark-mode query, web font.
The spread is what matters on this template: 100 in Superhuman against 70 in Outlook Classic, a 30-point gap across the same file. 7 of the 21 clients render it without a single flagged property. Outlook Classic is the one to preview against after any edit, because it is where this template has the least margin, and the 121 warnings behind that score are concentrated there rather than spread evenly.
At 12.8KB compiled it has roughly 89KB of headroom before Gmail clips the message at 102KB and hides the rest behind a "View entire message" link. Inlined CSS and base64 images both count toward that, so watch it as you add sections.
Safe to customise: The verification link and its expiry wording. Activation mail is read in a hurry with the signup form still open in another tab, so the link belongs above the fold and the expiry belongs next to it, not in the footer.
Leave alone: The plain-text fallback of the link. Some clients and most security scanners rewrite or strip the button href, and the visible URL underneath is what saves the activation when they do.
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