I have this setting in my init file:

--8<---------------cut here---------------start------------->8---
(when (window-system)
  (custom-set-variables
   '(modus-themes-slanted-constructs t)
   '(modus-themes-bold-constructs nil))
  (load-theme 'modus-operandi))
--8<---------------cut here---------------end--------------->8---

After upgrade the new version of modus-themes is merged on master, I get
the view attached as ‘emacs_1.png’.

If I comment-out the above lines in init file and then ‘M-x load-theme
RET modus-operandi RET’ after the startup, I get the view as in
‘emacs_2.png’.

Notice the font difference. And this difference is causing problems in
other areas. Like Gnus group buffer; the lines are not aligned properly.

Sorry for the image attachments.