Toolbar dropdown menu is not closing on click of toolbar button or clicked outside of tinymce editor

[testtwf]

Toolbar dropdown menu is not closing on click of toolbar button or clicked outside of editor. how to fix the issue.

NOTE : i'm using this version of tinymce -> tinymce": "^6.8.3
below is the configuration for tinymce editor-

tinymce.init({
	selector: 'textarea',
	placeholder: "Content",
	min_height: 300,
	promotion: false,
	branding: false,
	plugins: 'link lists anchor autoresize emoticons preview code',
	toolbar: 'undo redo | bold italic underline strikethrough superscript subscript| forecolor backcolor | \
		alignleft aligncenter alignright alignjustify | \
		bullist numlist outdent indent hr| \
		link emoticons | FileManager | customUppercase customLowercase',
	menubar: 'format',
	menu: {
		format: { title: 'Format', items: 'styles fontsize align lineheight | removeformat' },
	}
});

Screenshot & expected behavior