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An Update on the Litmus-Microsoft Partnership


Last August at Litmus Live, Microsoft and Litmus announced a historic partnership to help improve rendering in Outlook clients. We’re back with an update and behind-the-scenes look at how the partnership is going since the announcement.

How Microsoft is Working with Litmus to Improve Rendering

Kevin Mandeville (Product Manager at Litmus), and Justine Jordan (VP of Marketing at Litmus), meet with Outlook Program Manager Caitlin Hart on a regular basis to discuss bug reports and rendering to help prioritize the most important issues for Microsoft.

They also review progress on fixes and next steps for testing (and eventually, announcement!). It’s been a slow and steady process, with Microsoft leadership remaining 100% supportive of the initiative. You’re probably wondering when the first fixes will be announced. While we we’re not quite ready to reveal the first fixes slated for release, we can say that we’ve been testing some exciting changes. We can’t wait to share the first Outlook rendering fixes that will make email designers’ lives easier. Change takes time, and we’re confident it will be worth the wait.

What About Recent Rendering Regressions in and Outlook Apps?

As the wheels of change turn inside Microsoft, the Outlook team is shipping updates to their products faster. Bugs can be an unfortunate and unintentional side effect of otherwise positive momentum, and together with Microsoft we’re working to report these bugs and get them resolved as quickly as possible. In particular, we’re working to address image gaps in and lost responsive support in Outlook apps.

What’s most exciting is that this is the first time the email community has engaged in direct dialogue with Microsoft for email rendering bugs. Without this partnership and bugs submitted by the community, Microsoft would not be aware of these rendering issues or have access to real-world code and email examples. Your bug reports help the Outlook team identify where intended behavior is going wrong and develop solutions faster. As the partnership matures, so will the process for managing rendering across all clients.

Bugs Submitted So Far

There have been ~60 bugs reported so far, with the top bugs coming from desktop clients Outlook 2016 and Windows 10 Mail and webmail client The two most popular bugs reported have been missing support for background images and web fonts.


How to Submit Bugs to Microsoft

We need more bug reports!

You can report Outlook rendering bugs to the Litmus and Microsoft teams. We want to hear from you! Email, and be sure to include the following:

  • Full HTML email code
  • Screenshots of the rendering bug
  • Thorough descriptions of expected behavior versus actual behavior

No bug is too small (or repetitive) and Litmus Builder/Checklist links are acceptable as well.

You can also create tickets directly through Litmus Checklist. When viewing an Outlook client, click on the bug icon in the bottom right hand corner:


This will slide out a short form where you can describe the bug:


Reporting bugs in Litmus will automatically attach your HTML and screenshots, so no need to manually add them.

Thank You

Thank you to the entire email community for supporting the partnership with your patience, commitment, and passion!

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