diff --git a/Libraries/LibWeb/CSS/Selector.h b/Libraries/LibWeb/CSS/Selector.h
index f1ff146582..84f8ad21fa 100644
--- a/Libraries/LibWeb/CSS/Selector.h
+++ b/Libraries/LibWeb/CSS/Selector.h
@@ -63,6 +63,7 @@ public:
             None,
             HasAttribute,
             ExactValueMatch,
+            Contains,
         };
 
         AttributeMatchType attribute_match_type { AttributeMatchType::None };
diff --git a/Libraries/LibWeb/CSS/SelectorEngine.cpp b/Libraries/LibWeb/CSS/SelectorEngine.cpp
index 12470c5d8a..a2a89c911f 100644
--- a/Libraries/LibWeb/CSS/SelectorEngine.cpp
+++ b/Libraries/LibWeb/CSS/SelectorEngine.cpp
@@ -91,6 +91,10 @@ bool matches(const Selector::SimpleSelector& component, const Element& element)
         if (element.attribute(component.attribute_name) != component.attribute_value)
             return false;
         break;
+    case Selector::SimpleSelector::AttributeMatchType::Contains:
+        if (!element.attribute(component.attribute_name).split(' ').contains_slow(component.attribute_value))
+            return false;
+        break;
     default:
         break;
     }
diff --git a/Libraries/LibWeb/Dump.cpp b/Libraries/LibWeb/Dump.cpp
index 77c3acc95b..42ce636a19 100644
--- a/Libraries/LibWeb/Dump.cpp
+++ b/Libraries/LibWeb/Dump.cpp
@@ -242,6 +242,9 @@ void dump_selector(const Selector& selector)
             case Selector::SimpleSelector::AttributeMatchType::ExactValueMatch:
                 attribute_match_type_description = "ExactValueMatch";
                 break;
+            case Selector::SimpleSelector::AttributeMatchType::Contains:
+                attribute_match_type_description = "Contains";
+                break;
             }
 
             dbgprintf("%s:%s", type_description, simple_selector.value.characters());
diff --git a/Libraries/LibWeb/Parser/CSSParser.cpp b/Libraries/LibWeb/Parser/CSSParser.cpp
index 507ff8320d..a8ac658606 100644
--- a/Libraries/LibWeb/Parser/CSSParser.cpp
+++ b/Libraries/LibWeb/Parser/CSSParser.cpp
@@ -472,8 +472,13 @@ public:
             char expected_end_of_attribute_selector = ']';
             while (peek() != expected_end_of_attribute_selector) {
                 char ch = consume_one();
-                if (ch == '=') {
-                    attribute_match_type = Selector::SimpleSelector::AttributeMatchType::ExactValueMatch;
+                if (ch == '=' || (ch == '~' && peek() == '=')) {
+                    if (ch == '=') {
+                        attribute_match_type = Selector::SimpleSelector::AttributeMatchType::ExactValueMatch;
+                    } else if (ch == '~') {
+                        consume_one();
+                        attribute_match_type = Selector::SimpleSelector::AttributeMatchType::Contains;
+                    }
                     attribute_name = String::copy(buffer);
                     buffer.clear();
                     in_value = true;