Javascript 错误类型错误：无法获取属性'；0'；未定义引用或空引用-当在控制台中的HTML_元素上单击（）时

尝试在控制台中执行以下代码时出错：

document.getElementsByClassName("pi pi-chevron-right")[0].click();

代码执行它应该执行的操作，但每次执行click（）方法时都会输出错误

错误消息：

document.getElementsByClassName("pi pi-chevron-right")[0].click();
undefined
ERROR TypeError: Unable to get property '0' of undefined or null reference
   "ERROR"
   {
      [functions]: ,
      __proto__: { },
      description: "Unable to get property '0' of undefined or null reference",
      message: "Unable to get property '0' of undefined or null reference",
      name: "TypeError",
      number: -2146823281,
      stack: "TypeError: Unable to get property '0' of undefined or null reference
   at e.prototype.onClick (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:5086814)
   at Anonymous function (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:5106159)
   at handleEvent (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:1197790)
   at handleEvent (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:1208980)
   at Uf (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:1167505)
   at Anonymous function (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:1173798)
   at Anonymous function (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:2655047)
   at e.prototype.invokeTask (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:68805)
   at onInvokeTask (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:1131800)
   at e.prototype.invokeTask (https://ghc.connect.pwc.com/main.058cd423c1cf54028b93.js:1:68805)",
      Symbol()_i.t1si0nbd5nz: undefined,
      Symbol()_j.t1si0nbd5nz: undefined,
      Symbol()_l.t1si0nbd5nz: undefined,
      Symbol(INITIAL_VALUE)_h.t1si0nbd5nz: undefined,
      Symbol(observable)_n.t1si0nbd5nz: undefined,
      Symbol(react.element)_m.t1si0nbd5nz: undefined,
      Symbol(rxSubscriber)_g.t1si0nbd5nz: undefined,
      Symbol(rxSubscriber)_o.t1si0nbd5nz: undefined,
      Symbol(test)_k.t1si0nbd5nz: undefined
   }

我想单击以下用蓝色标记的UI元素“>”：

UI元素的代码如下所示：

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function handler() {
    const elements = document.getElementsByClassName("pi pi-chevron-right");
    if (elements && elements[0]) {
        elements[0].click();
    } else {
        console.error('Element not found!')
    }
}