Free StopWatch 4.0.0.0, the expansion-triangle should be white, but it is grey

Reproduction steps

• install Free StopWatch 4.0.0.0 from rapps
• select from menubar the options-tab
• watch closely the expansion-triangle for "languages"

Expected result
the triangles background should be drawn white 2K3SP2.png
when hovered over, the triangles background should be drawn in light-blue 2k3sp2_expectedResultWhenHovered.webm

Observed result
the triangles background is drawn grey 0.4.14-RC-98-gc437ff6.png
when hovered over, the triangles background is drawn in black 0.4.14-RC-98-gc437ff6_observedResultWhenHovered.webm
the log is useless 0.4.14-RC-98-gc437ff6.log Nothing gets logged when interacting with that stuff