Shadow DOM: Slots and fallback contents

third_party/blink/web_tests/external/wpt/shadow-dom/slot-fallback-content-004-ref.html

149.0.7827.2213 B

Test passes if there is one line of text "SLOT1" below.

SLOT1

Test passes if empty.

Test passes if there is one line of text "SLOT3" below.

SLOT3

Test passes if there is one line of text "SLOT4" below.

SLOT4