Scroll Progress Indicator by rugby

/* ==UserStyle==
@name           Scroll Progress Indicator
@namespace      rugby
@version        1.0.0
@description    Shows a progress bar on top of web pages measuring scrolling progress
@license        MIT
@preprocessor   uso
@var            color color Color #0078d7
@var            range height Height [2, 1, 10, 1, "px"]
==/UserStyle== */

@-moz-document url-prefix("http") {
  @keyframes progress {
    from {
      transform: scaleX(0);
    }
    to {
      transform: scaleX(1);
    }
  }
  html {
    scroll-timeline: --page-scroll block;
  }
  html:not(:fullscreen):not([stylus-iframe]):before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    z-index: 999999;
    width: 100%;
    height: /*[[height]]*/;
    transform: scaleX(0);
    transform-origin: 0 50%;
    background-color: /*[[color]]*/;
    box-shadow: 0 0 3px /*[[color]]*/;
    animation: progress auto linear;
    animation-timeline: --page-scroll;
  }
}