inactiveStyle Opacity not working in Canary

I'm trying to tone down the icon's color on inactive tabs but can't seem to get it to work, I'd like to set the opacity to 0.5 but regardless of whether I set it to 0, 1, or 0.5 it doesn't change. Do I have this configured correctly?

// hyper-tab-icons
tabIcons: {
    activeStyle: {
        display: 'inline-block',
        marginRight: '0.25rem',
        transition: 'opacity 200ms ease-in',
        verticalAlign: 'middle',
        width: '1rem',
    },
    inactiveStyle: {
        opacity: 0.5,
    },
    // mapIcons: {
    //  nodejs: ['node'],
    //  docker: ['docker-compose'],
    // },
    // disableColors: 'false',
    mapColors: {
        bash: 'hsl(127, 49%, 46%)',
        docker: 'hsl(194, 88%, 49%)',
        'docker-compose': 'hsl(194, 88%, 49%)',
        fish: 'hsl(357, 63%, 56%)',
        nodejs: 'hsl(80, 100%, 37%)',
        node: 'hsl(80, 100%, 37%)',
        npm: 'hsl(357, 70%, 44%)',
        rails: 'hsl(0, 100%, 40%)',
        ruby: 'hsl(2, 63%, 48%)',
        shell: 'hsl(0, 0%, 0%)',
        zsh: 'hsl(66, 100%, 42%)',
        python: 'hsl(48, 100%, 67%)',
        vim: 'hsl(120, 100%, 25%)',
        yarn: 'hsl(198, 61%, 45%)',
    }
}

Right now I've got it set by doing an override in the CSS but I'm not sure what's up. Full configuration

I also noticed that having disableColors set, regardless of true or false values seems to enable it, the only way to disable it seems to be to not set it either way if I understand what it's supposed to be doing correctly.

dfrankland / hyper-tab-icons

inactiveStyle Opacity not working in Canary #37