Method push

packages/parse5/lib/parser/open-element-stack.ts:81–94

(element: T['element'], tagID: $)

    //Mutations
    push(element: T['element'], tagID: $): void {
        this.stackTop++;

        this.items[this.stackTop] = element;
        this.current = element;
        this.tagIDs[this.stackTop] = tagID;
        this.currentTagId = tagID;

        if (this._isInTemplate()) {
            this.tmplCount++;
        }

        this.handler.onItemPush(element, tagID, true);
    }

    pop(): void {
        const popped = this.current;