虽然这里提供的CSS解决方案有效，

对于任何喜欢使用Bootstrap 4方式的人，就像官方Bootstrap主题指南中建议的那样， 这应该会有帮助:

按你们的习惯。SCSS文件(参见上面的指南^)，其中您添加了您的变量覆盖，添加以下变量来删除按钮的盒子阴影:

// import bootstrap's variables & functions to override them
@import "node_modules/bootstrap/scss/functions";
@import "node_modules/bootstrap/scss/variables";
@import "node_modules/bootstrap/scss/mixins";

// override the variables you want (you can look them up in node_modules/bootstrap/scss/variables file, they're the ones that have the !default keyword at the end)
$btn-focus-box-shadow: none;

// option A: include all of Bootstrap (see the above guide for other options)
@import "node_modules/bootstrap/scss/bootstrap";

这对我很有用。

请注意，在bootstrap的变量文件中有许多变量用于box-shadow，也用于其他控件，所以如果你想使用它们和/或这个特定的变量不适合你，可能需要更多的研究。

与TS溶液反应

  const btnRef = useRef<HTMLButtonElement | null>(null);
  const handleOnMouseUp = () => {
    btnRef.current?.blur();
  };
  
  <button
    ref={btnRef}
    onClick={handleOnClick}
    onMouseUp={handleOnMouseUp}
  >
    <span className="icon-plus"></span> Add Page
  </button>

我在另一个页面上找到了这个问题和回答，覆盖按钮焦点样式对我有用。这个问题可能是Chrome的MacOS特有的。

.btn:focus {
  outline: none;
  box-shadow: none;
}

请注意，这对可访问性有影响，除非你的按钮和输入有一个良好的一致的焦点状态，否则不建议这样做。根据下面的评论，有些用户不能使用鼠标。

您可以使用按钮的焦点事件。 这适用于angular的情况

<button (focus)=false >Click</button

I found the same situation using a submit button in a form using a bootstrap (v4.4.1) class. The problem arose as I was building a single-page user interface using JavaScript to manipulate all the required changes to the DOM. The form data was submitted to the server via 'fetch' using a JSON string rather than a HTTP POST request. Note that usually the form's default behaviour is to reload the document, and normally this would refresh the button, however the form's default behaviour was prevented by using e.preventDefault() in the listener function for the form's submit event (it is a single-page UI so the document is never reloaded and traffic to the server is minimised to data only). Given the document was not reloaded the button appeared to stay depressed until the user clicked elsewhere in the window. This is what I had (with the problem):

<输入类型=“submit”类=“btn btn-primary”>

这是我用来解决按钮一直按下的问题:

<input type=“submit” class=“btn btn-primary” onmouseup=“this.blur（）”>

有点核，但这是我在Angular 9上工作的简单方法。使用与因果关系，因为它影响每个html元素。

*:focus {
  outline: 0 !important;
}