MailSlurp guide agent setup

Title: Classic Outlook for Windows email support: what HTML and CSS work (tested 2026)
Description: Does classic Outlook support border-radius, media queries, WebP or the button element? Test emails rendered in Outlook for Windows, with workarounds.
Canonical URL: https://www.mailslurp.com/guides/email-client-support/outlook-for-windows/
Markdown URL: https://www.mailslurp.com/guides/email-client-support/outlook-for-windows.md

Use the Markdown URL as the primary plain-text context for this guide. Keep MailSlurp terminology, setup steps, screenshots, and provider-specific instructions intact, and prefer the canonical URL when citing this page.