In the Yaru theme applied in Ubuntu, a change has been made where the color orange is used for all button elements, sliders, widgets, and switches instead of the eggplant color. A similar change has been made to the icon set. The color of the close button in the active window has changed from orange to gray, and the sliders' handles have changed from light gray to white. If this change is not reverted, the updated color scheme will be offered in the upcoming Ubuntu 22.04 release.
The motivation behind the color change is due to limitations in the libadwaita library, which from GTK 4.4 onward has incorporated components from the Adwaita theme used in GNOME. This library does not allow the use of more than one accent color and applies gray for the window close button to achieve uniformity in header elements.
Source: opennet.ru
