Additional uncaught exception thrown while handling exception.

Original

Error: Class 'Drupal\Core\Template\Attribute' not found in template_preprocess_html() (line 1299 of /home/hoshinonline/public_html/core/includes/theme.inc).

template_preprocess_html(Array, 'html', Array) (Line: 287)
Drupal\Core\Theme\ThemeManager->render('html', Array) (Line: 431)
Drupal\Core\Render\Renderer->doRender(Array, 1) (Line: 200)
Drupal\Core\Render\Renderer->render(Array, 1) (Line: 144)
Drupal\Core\Render\Renderer->Drupal\Core\Render\{closure}() (Line: 573)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 145)
Drupal\Core\Render\Renderer->renderRoot(Array) (Line: 66)
Drupal\Core\Render\BareHtmlPageRenderer->renderBarePage(Array, Object, 'install_page', Array) (Line: 76)
Drupal\Core\ProxyClass\Render\BareHtmlPageRenderer->renderBarePage(Array, Object, 'install_page', Array) (Line: 1061)
install_display_output(Array, Array) (Line: 159)
install_drupal(Object) (Line: 44)

Additional

LogicException: A stray renderRoot() invocation is causing bubbling of attached assets to break. in Drupal\Core\Render\Renderer->renderRoot() (line 138 of /home/hoshinonline/public_html/core/lib/Drupal/Core/Render/Renderer.php).

Drupal\Core\Render\Renderer->renderRoot(Array) (Line: 66)
Drupal\Core\Render\BareHtmlPageRenderer->renderBarePage(Array, 'Error', 'install_page', Array) (Line: 76)
Drupal\Core\ProxyClass\Render\BareHtmlPageRenderer->renderBarePage(Array, 'Error', 'install_page', Array) (Line: 1061)
install_display_output(Array, Array, Array) (Line: 267)
_drupal_log_error(Array, 1) (Line: 618)
_drupal_exception_handler(Object)