Allows focus styles to be applied to elements like buttons and form controls, only when they are focused using the keyboard (e.g. when tabbing between elements), and not when they are focused using a mouse or other pointing device. See <a data-l10n-name="bugzilla">bug 1617600</a> for more details.
仅在使用键盘聚焦于按钮和表单控件等元素（例如：使用 Tab 键切换）时，允许聚焦样式生效。鼠标或其他指针设备则禁止。欲详细了解，请参阅 <a data-l10n-name="bugzilla">Bug 1617600</a>。