Kirigami.Icon { isMask: true } flattens an SVG to its alpha, so when a quick-setting tile resolves to a colored preferences/scalable glyph the whole rounded background collapses into a solid square. Append -symbolic to the five icon names that collided with colored tiles and add symlink aliases where no real symbolic variant exists yet. Guard the regression with a check in tests/check-shift-icon-theme.sh.
