plugins slider
this is a semi-bug, or an anti-feature. I'm running xfce 4.16 in slackware 15.0. Plugins like "power-manager-plugin-5" or "pulseaudio" include sliders for things such as brightness adjustment, volumes ... To be able to quickly change the value from max. to min. for example, the slider needs to be caught by the mouse pointer and dragged. Clicking on the desired position of the "bar" will make the slider progressively and slowly move to reach the desired position. For KDE, it jumps in one click to the position pointed by the mouse. In windows 7 it will jump of a quarter of the whole bar length. Therefore i think at least there should be an option to allow moving the slider to any position with just one click.
Above all, in xfce, even while the slider is caught and held by the mouse pointer, the slider does not smoothly follow the pointer. In the case of pulseaudio it is a lot worse and clearly looks like a bug as the slider move by doing big ups and downs, sometimes it suddenly jumps by half of the bar length to an undesired position. This particular problem is seen when using Adwaita theme.
option "gtk-primary-button-warps-slider = false" is already set in ~/.config/gtk-3.0/settings.ini.
Adwaita theme must be used.