Currently it's not possible to hide the menu bar by press Ctrl+m. Most Plasma/KDE applications support has this feature. Thank you for your great work guys!
Well, in my case it's the other way around. Kontact does not show a menu and I can't evoke it with Ctrl+M.
Git commit b42ebb06b1bd0160776cbae795e86030c4445694 by Laurent Montel. Committed on 25/10/2022 at 05:23. Pushed by mlaurent into branch 'master'. Fix bug 431308: Hide Menu by Ctrl+M FIXED-IN: 5.22.0 M +5 -0 src/kontact.kcfg M +2 -1 src/kontactui.rc M +26 -0 src/mainwindow.cpp M +4 -1 src/mainwindow.h https://invent.kde.org/pim/kontact/commit/b42ebb06b1bd0160776cbae795e86030c4445694