Vivaldi UI scrolls with highlight color

[Hadden89]

Relative of the ones for borders and webpages scrolls.
Use highlight color for the UI scrollbar moving part.
Useful especially for dark themes.
Only tested on windows.

/* UI scrollbars with highlight color */
#browser ::-webkit-scrollbar-thumb {
	background-color: var(--colorHighlightBgDark) !important;
}
#browser ::-webkit-scrollbar-thumb:hover,
#browser ::-webkit-scrollbar-thumb:active {
	background-color: var(--colorHighlightBg) !important;
}

[Gaëlle]

Really nice! Thanks for sharing

[tam710562]

@Hadden89 Quite interesting to use with --colorAccentBg