discourse/plugins/discourse-lazy-videos/assets/javascripts/discourse/components/lazy-video.hbs

<div
  class={{concat-class
    "lazy-video-container"
    (concat @videoAttributes.providerName "-onebox")
    (if this.isLoaded "video-loaded")
  }}
  data-video-id={{@videoAttributes.id}}
  data-video-title={{@videoAttributes.title}}
  data-video-start-time={{@videoAttributes.startTime}}
  data-provider-name={{@videoAttributes.providerName}}
>
  {{#if this.isLoaded}}
    <LazyIframe
      @providerName={{@videoAttributes.providerName}}
      @title={{@videoAttributes.title}}
      @videoId={{@videoAttributes.id}}
      @startTime={{@videoAttributes.startTime}}
    />
  {{else}}
    <div
      class={{concat-class "video-thumbnail" @videoAttributes.providerName}}
      tabindex="0"
      style={{this.thumbnailStyle}}
      {{on "click" this.loadEmbed}}
      {{on "keypress" this.loadEmbed}}
    >
      <img
        class={{concat @videoAttributes.providerName "-thumbnail"}}
        src={{@videoAttributes.thumbnail}}
        title={{@videoAttributes.title}}
        loading="lazy"
      />
      <div
        class={{concat-class
          "icon"
          (concat @videoAttributes.providerName "-icon")
        }}
      ></div>
    </div>
    <div class="title-container">
      <div class="title-wrapper">
        <a
          target="_blank"
          rel="noopener noreferrer"
          class="title-link"
          href={{@videoAttributes.url}}
          title={{@videoAttributes.title}}
        >
          {{@videoAttributes.title}}
        </a>
      </div>
    </div>
  {{/if}}
</div>