xfce_titled_dialog_new_with_buttons()
or xfce_spawn_on_screen()
)Please don't take the issues listed on the milestone pages as obligatory. Keep in mind that they may or may not make it into the 4.20 release, depending on the time the individual developers have.
Sumup GitLab Milestone for 4.20
For quick access, open 4.20 issues by component: