in Ubuntu 21.10 Approved Termination of the delivery topic, combining dark headlines, light background and light controls. The users will be offered by default completely light version of the topic yaru , as well as the possibility of switching to a fully dark version (Dark headers, dark background and dark Controls).
Solution is explained The absence of different colors of the background and text for the header and the main window is explained in GTK3 and GTK4 does not allow to guarantee the correct operation of all GTK applications when using combined topics (for example, in GNOME Disk Analyser in a dark header appears White input bar). Another reason is too large labor costs for the maintenance of non-standard topics. The problem is that GNOME does not provide the official programming interface and a set of recommendations for the topics of GTK, which leads to a violation of third-party compatibility in each new GNOME release.
From other changes expected in Ubuntu 21.10, is noted Care from using eggplant color for the background of the switches and widgets ( The replacement color is not yet approved).