Linux Mint forks GNOME’s Libadwaita to add theme support
On numerous occasions, we've talked about the issue facing non-GNOME GTK desktops, like Xfce, MATE, and Cinnamon: the popularity of Libadwaita. With more and more application developers opting for GNOME's Libadwaita because of the desktop environment's popularity, many popular GTK applications now look like GNOME applications
https://www.osnews.com/story/142412/linux-mint-forks-gnomes-libadwaita-to-add-theme-support/