        link.className = "expander"
                        let that = this
                        link.onclick = function () {
                            if (rootDf.expandedFrames.has(frameId))
                                rootDf.expandedFrames.delete(frameId)
                            else rootDf.expandedFrames.add(frameId)
                            that.renderTable(id)
                        }
                        link.appendChild(this.createExpander(expanded))
                        link.i