代码片段求助——嵌入块面包屑隐藏，前 3 层、文档本层路径

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(()=>{
    // 监听面包屑项出现
    observeElementExist('.protyle-wysiwyg__embed .protyle-breadcrumb__bar .protyle-breadcrumb__item:first-child', async (breadcrumb) => {
        if(!breadcrumb.closest(".protyle-wysiwyg__embed .protyle-breadcrumb__bar.protyle-breadcrumb__bar--nowrap .protyle-breadcrumb__item:first-child")) return;
        const breadcrumbText = breadcrumb.querySelector(".protyle-breadcrumb__text");
        if(!breadcrumbText) return;
        const text = breadcrumbText.textContent;
        const parts = text.split('/');
        let result = [];
        if (parts.length >= 3) {
          result = parts.slice(3);
        } else {
            return; // 不足3项不处理
        }
        // 当面包屑第二个箭头的标题和第一个箭头的标题相同时过滤掉
        const breadcrumbBar = breadcrumb.parentElement;
        let nextText = breadcrumbBar?.querySelectorAll(".protyle-breadcrumb__text");
        if(!breadcrumbBar || !nextText || !nextText[1]) return;
        nextText = nextText[1];
        result = result.filter(item => item.trim() !== nextText.textContent.trim());
        // 当面包屑第一个箭头的标题和文档标题相同时过滤掉
        let doc = await query(`select content from blocks where id = '${breadcrumb.dataset.id}'`);
        doc = doc[0] || {};
        result = result.filter(item => item.trim() !== doc.content.trim());
        //重新输出面包屑
        const finalResult = result.join('/');
        breadcrumbText.textContent = finalResult;
    }, document.body);

    // 查询SQL函数
    async function query(sql) {
        const result = await requestApi('/api/query/sql', { "stmt": sql });
        if (result.code !== 0) {
            console.error("查询数据库出错", result.msg);
            return [];
        }
        return result.data;
    }

    async function requestApi(url, data, method = 'POST') {
        return await (await fetch(url, {method: method, body: JSON.stringify(data||{})})).json();
    }

    // 监听元素出现
    function observeElementExist(selector, callback, observeNode) {
        const handleMutations = (mutationsList, observer) => {
            for (let mutation of mutationsList) {
                if (mutation.type === 'childList') {
                    mutation.addedNodes.forEach(node => {
                        if(!node || node.nodeType !== Node.ELEMENT_NODE) return;
                        if (node.matches && node.matches(selector)) {
                            callback(node);
                        } else if (node.querySelector(selector)) {
                            const nodes = node.querySelectorAll(selector);
                            nodes.forEach(node => {
                                callback(node);
                            });
                        }
                    });
                }
            }
        };
  
        // 创建一个MutationObserver实例
        const config = { attributes: false, childList: true, subtree: true };
        const observer = new MutationObserver(handleMutations);
  
        // 选择需要监听的父节点
        observeNode = typeof observeNode === 'string' ? document.querySelector(observeNode) : observeNode;
        const targetNode = observeNode || document.body;
  
        // 开始监听目标节点的变化
        observer.observe(targetNode, config);
    }
})();