siyuan/app/src/protyle/util/addStyle.ts

export const addStyle = (url: string, id: string) => {
    if (!document.getElementById(id)) {
        const styleElement = document.createElement("link");
        styleElement.id = id;
        styleElement.rel = "stylesheet";
        styleElement.type = "text/css";
        styleElement.href = url;
        document.getElementsByTagName("head")[0].appendChild(styleElement);
    }
};