Rocket.Chat/app/ui-utils/client/lib/alerts.html

<template name="alerts">
	<div class="rc-alerts {{modifiers}} {{customclass}}" data-popover="popover">
		{{#if icon}}
			<div class="rc-alerts__big-icon rc-alerts__icon {{hasAction}} js-action">
				{{> icon icon=icon }}
			</div>
		{{/if}}
		<div class="rc-alerts__content {{hasAction}} js-action">
			{{#if template}}
				{{> Template.dynamic template=template data=data}}
			{{else}}
				{{#if title}}
					<div class="rc-alerts__title">
						{{title}}
					</div>
				{{/if}}
				<div class="rc-alerts__line">
					{{text}}
				</div>
				{{{html}}}
			{{/if}}
		</div>
		{{#if closable}}
			<div class="rc-alerts__icon js-close" aria-label="{{_ "Close"}}">
				{{> icon block="rc-alerts__icon rc-alerts__icon--close" icon='plus'}}
			</div>
		{{/if}}
	</div>
</template>