in src/lib/CodeMirror/indentationMarkers.ts [397:406]
function createGradient(
markerCssProperty: string,
indentWidth: number,
startOffset: number,
columns: number
) {
const gradient = `repeating-linear-gradient(to right, var(${markerCssProperty}) 0 ${MARKER_THICKNESS}, transparent ${MARKER_THICKNESS} ${indentWidth}ch)`;
// Subtract one pixel from the background width to get rid of artifacts of pixel rounding
return `${gradient} ${startOffset * indentWidth}.5ch/calc(${indentWidth * columns}ch - 1px) no-repeat`;
}