Version: 1.0.1
This theme is based on Apple Mail (iMail/iCloud Mail)
I used Jamie Wilson’s (http://jamiewilson.io) Darkside theme as a base template.
Only tested on Windows.
Requirements
Requires Mailspring avatars addon
Download
Note: I am not affiliated with apple at all
Hey does this theme work for Macos?
Yes. It should work. I have only tested on Windows. Please Tell me if there are any problems.
okay thank you I will let you know
Great and I might download a VM for Linux and Mac to test it out
That is a good idea for testing
Quick message to let you know I couldn’t get this theme to install on mailspring on mac. It said:
The plugin or theme you selected has not been upgraded to support Mailspring. If you’re the developer, update the package.json’s engines field to include “mailspring”.
For more information, see this migration guide: http://support.getmailspring.com/hc/en-us/articles/115001918391
I’ll try and test it out again when it’s updated 
had the same issue.
you can just add
“mailspring” : “*”
in the package.json under the “engines” section until it is fixed
Thanks for the heads up!
I actually tried that but couldn’t get it to work the first time. Didn’t realize the problem was that it was missing a space between “mailspring” and the “:” - working now!
Thank you! I fixed it. While working on the theme, I installed it by moving the folder in the packages directory.
It’s work fine in a MacBook Air 2020 with macOS Monterey.
Could you create a new one for the DARK Apple theme 
Any chance of a dark version of the macOS theme?
Yes, a DARK Apple version would be nice to have! Especially if you can switch between dark/light for the message body itself (like the Outlook Mail client does on a Mac).
I came here to also request Dark Theme support… might give my hands at it and see what I can do with Color - Foundations - Human Interface Guidelines - Design - Apple Developer
Thanks for making the theme… this is great!!
p.s. - @Apple last seen Nov 1, '22 
I can confirm this bug happens on linux.
