diff --git a/Userland/Libraries/LibWeb/CSS/Display.cpp b/Userland/Libraries/LibWeb/CSS/Display.cpp
index 45844cef7f..b8370d7101 100644
--- a/Userland/Libraries/LibWeb/CSS/Display.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Display.cpp
@@ -8,98 +8,98 @@
 
 namespace Web::CSS {
 
-DeprecatedString Display::to_deprecated_string() const
+ErrorOr<String> Display::to_string() const
 {
     StringBuilder builder;
     switch (m_type) {
     case Type::OutsideAndInside:
         switch (m_value.outside_inside.outside) {
         case Outside::Block:
-            builder.append("block"sv);
+            TRY(builder.try_append("block"sv));
             break;
         case Outside::Inline:
-            builder.append("inline"sv);
+            TRY(builder.try_append("inline"sv));
             break;
         case Outside::RunIn:
-            builder.append("run-in"sv);
+            TRY(builder.try_append("run-in"sv));
             break;
         }
-        builder.append(' ');
+        TRY(builder.try_append(' '));
         switch (m_value.outside_inside.inside) {
         case Inside::Flow:
-            builder.append("flow"sv);
+            TRY(builder.try_append("flow"sv));
             break;
         case Inside::FlowRoot:
-            builder.append("flow-root"sv);
+            TRY(builder.try_append("flow-root"sv));
             break;
         case Inside::Table:
-            builder.append("table"sv);
+            TRY(builder.try_append("table"sv));
             break;
         case Inside::Flex:
-            builder.append("flex"sv);
+            TRY(builder.try_append("flex"sv));
             break;
         case Inside::Grid:
-            builder.append("grid"sv);
+            TRY(builder.try_append("grid"sv));
             break;
         case Inside::Ruby:
-            builder.append("ruby"sv);
+            TRY(builder.try_append("ruby"sv));
             break;
         }
         if (m_value.outside_inside.list_item == ListItem::Yes)
-            builder.append(" list-item"sv);
+            TRY(builder.try_append(" list-item"sv));
         break;
     case Type::Internal:
         switch (m_value.internal) {
         case Internal::TableRowGroup:
-            builder.append("table-row-group"sv);
+            TRY(builder.try_append("table-row-group"sv));
             break;
         case Internal::TableHeaderGroup:
-            builder.append("table-header-group"sv);
+            TRY(builder.try_append("table-header-group"sv));
             break;
         case Internal::TableFooterGroup:
-            builder.append("table-footer-group"sv);
+            TRY(builder.try_append("table-footer-group"sv));
             break;
         case Internal::TableRow:
-            builder.append("table-row"sv);
+            TRY(builder.try_append("table-row"sv));
             break;
         case Internal::TableCell:
-            builder.append("table-cell"sv);
+            TRY(builder.try_append("table-cell"sv));
             break;
         case Internal::TableColumnGroup:
-            builder.append("table-column-group"sv);
+            TRY(builder.try_append("table-column-group"sv));
             break;
         case Internal::TableColumn:
-            builder.append("table-column"sv);
+            TRY(builder.try_append("table-column"sv));
             break;
         case Internal::TableCaption:
-            builder.append("table-caption"sv);
+            TRY(builder.try_append("table-caption"sv));
             break;
         case Internal::RubyBase:
-            builder.append("ruby-base"sv);
+            TRY(builder.try_append("ruby-base"sv));
             break;
         case Internal::RubyText:
-            builder.append("ruby-text"sv);
+            TRY(builder.try_append("ruby-text"sv));
             break;
         case Internal::RubyBaseContainer:
-            builder.append("ruby-base-container"sv);
+            TRY(builder.try_append("ruby-base-container"sv));
             break;
         case Internal::RubyTextContainer:
-            builder.append("ruby-text-container"sv);
+            TRY(builder.try_append("ruby-text-container"sv));
             break;
         }
         break;
     case Type::Box:
         switch (m_value.box) {
         case Box::Contents:
-            builder.append("contents"sv);
+            TRY(builder.try_append("contents"sv));
             break;
         case Box::None:
-            builder.append("none"sv);
+            TRY(builder.try_append("none"sv));
             break;
         }
         break;
     };
-    return builder.to_deprecated_string();
+    return builder.to_string();
 }
 
 }
diff --git a/Userland/Libraries/LibWeb/CSS/Display.h b/Userland/Libraries/LibWeb/CSS/Display.h
index 294846d108..5d041b6285 100644
--- a/Userland/Libraries/LibWeb/CSS/Display.h
+++ b/Userland/Libraries/LibWeb/CSS/Display.h
@@ -7,7 +7,7 @@
 #pragma once
 
 #include <AK/Assertions.h>
-#include <AK/DeprecatedString.h>
+#include <AK/String.h>
 
 namespace Web::CSS {
 
@@ -16,7 +16,7 @@ public:
     Display() = default;
     ~Display() = default;
 
-    DeprecatedString to_deprecated_string() const;
+    ErrorOr<String> to_string() const;
 
     bool operator==(Display const& other) const
     {
diff --git a/Userland/Libraries/LibWeb/DOM/Element.cpp b/Userland/Libraries/LibWeb/DOM/Element.cpp
index 57704c1631..84227f7a35 100644
--- a/Userland/Libraries/LibWeb/DOM/Element.cpp
+++ b/Userland/Libraries/LibWeb/DOM/Element.cpp
@@ -318,7 +318,7 @@ JS::GCPtr<Layout::Node> Element::create_layout_node_for_display_type(DOM::Docume
             return document.heap().allocate_without_realm<Layout::InlineNode>(document, element, move(style));
         if (display.is_flex_inside())
             return document.heap().allocate_without_realm<Layout::Box>(document, element, move(style));
-        dbgln_if(LIBWEB_CSS_DEBUG, "FIXME: Support display: {}", display.to_deprecated_string());
+        dbgln_if(LIBWEB_CSS_DEBUG, "FIXME: Support display: {}", MUST(display.to_string()));
         return document.heap().allocate_without_realm<Layout::InlineNode>(document, element, move(style));
     }
 
diff --git a/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp b/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp
index 2ad2b0b58d..f94cb6dfca 100644
--- a/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp
+++ b/Userland/Libraries/LibWeb/Layout/FormattingContext.cpp
@@ -161,7 +161,7 @@ OwnPtr<FormattingContext> FormattingContext::create_independent_formatting_conte
     // The child box is a block container that doesn't create its own BFC.
     // It will be formatted by this BFC.
     if (!child_display.is_flow_inside()) {
-        dbgln("FIXME: Child box doesn't create BFC, but inside is also not flow! display={}", child_display.to_deprecated_string());
+        dbgln("FIXME: Child box doesn't create BFC, but inside is also not flow! display={}", MUST(child_display.to_string()));
         // HACK: Instead of crashing, create a dummy formatting context that does nothing.
         // FIXME: Remove this once it's no longer needed. It currently swallows problem with standalone
         //        table-related boxes that don't get fixed up by CSS anonymous table box generation.