viousScrollData.visibleEntryTop=t.target.offsetTop,this._process(e(t))},i=(this._rootElement||document.documentElement).scrollTop,n=i>=this._previousScrollData.parentScrollTop;this._previousScrollData.parentScrollTop=i;for(const o of t){if(!o.isIntersecting){this._activeTarget=null,this._clearActiveClass(e(o));continue}const t=o.target.offsetTop>=this._previousScrollData.visibleEntryTop;if(n&&t){if(s(o),!i)return}else n||t||s(o)}}_initializeTargetsAndObservables(){this._targetLinks=new Map,this....