Hey thanks for opening your first issue, you did great :) Let's see if we can figure out what's going on together.

They must have updated their render engine recently as I have not noticed this issue in the past.

Can you tell me more about this? When did you see it working last? When did you start seeing this issue?

So far I have been using a workaround fix by adding a bgcolor attribute to the button-td tag, but of course this swallows up the corner radius.

What do you mean by this? Outlook on Windows doesn't support border-radius, so these buttons should have always been squared. Is that not the case on your end?

Unfortunately I don't have a copy of Microsoft 365 Outlook on Windows. I used Email on Acid to preview the template on Outlook Office 365 Windows 10, but but is what I see:

• I saw this issue for the first time on August 2nd. I saw it working properly on July 20th.
• To clarify, the Outlook button corners have always been square and continue to be square. Using the bgcolor attribute workaround removes the corner radii for other email clients. I could set up some conditional code to show a different button on Outlook vs. all other clients, but I'd consider that a last ditch resort due to the extra complexity involved.

I saw this issue for the first time on August 2nd. I saw it working properly on July 20th.

Can you tell me a little about your setup? Are you using a work computer on a company network? Do you know if there was a software update around that time?

Could something have changed on your system or network, like an admin pushing a software update or changing a network rule, something out of your control and/or knowledge?

Also do you know if anyone else is experiencing this? Outside of your team?