$page->html = '<h2>A Header</h2><p>Some <strong>bold</strong> content.</p>';
$page->save();
$resp = $this->asAdmin()->get($page->getUrl('/edit?editor=markdown-clean'));
$resp->assertStatus(200);
$resp->assertSee("## A Header\n\nSome **bold** content.");
$page->html = '<h2>A Header</h2><p>Some <strong>bold</strong> content.</p>';
$page->save();
$resp = $this->asAdmin()->get($page->getUrl('/edit?editor=markdown-clean'));
$resp->assertStatus(200);
$resp->assertSee("## A Header\n\nSome **bold** content.");