diff --git a/Userland/Libraries/LibWeb/HTML/MimeType.cpp b/Userland/Libraries/LibWeb/HTML/MimeType.cpp
index 30e20dfc369..e99231197e6 100644
--- a/Userland/Libraries/LibWeb/HTML/MimeType.cpp
+++ b/Userland/Libraries/LibWeb/HTML/MimeType.cpp
@@ -11,9 +11,9 @@
 
 namespace Web::HTML {
 
-MimeType::MimeType(JS::Realm& realm, String const& type)
+MimeType::MimeType(JS::Realm& realm, String type)
     : Bindings::PlatformObject(realm)
-    , m_type(type)
+    , m_type(move(type))
 {
 }
 
@@ -38,7 +38,7 @@ String const& MimeType::type() const
 JS::ThrowCompletionOr<String> MimeType::description() const
 {
     // The MimeType interface's description getter steps are to return "Portable Document Format".
-    static String description_string = TRY_OR_THROW_OOM(vm(), String::from_utf8("Portable Document Format"sv));
+    static String description_string = TRY_OR_THROW_OOM(vm(), "Portable Document Format"_string);
     return description_string;
 }
 
@@ -46,7 +46,7 @@ JS::ThrowCompletionOr<String> MimeType::description() const
 String const& MimeType::suffixes() const
 {
     // The MimeType interface's suffixes getter steps are to return "pdf".
-    static String suffixes_string = String::from_utf8_short_string("pdf"sv);
+    static String suffixes_string = "pdf"_short_string;
     return suffixes_string;
 }
 
diff --git a/Userland/Libraries/LibWeb/HTML/MimeType.h b/Userland/Libraries/LibWeb/HTML/MimeType.h
index 859e15dbf6b..29dd08a7f86 100644
--- a/Userland/Libraries/LibWeb/HTML/MimeType.h
+++ b/Userland/Libraries/LibWeb/HTML/MimeType.h
@@ -23,7 +23,7 @@ public:
     JS::NonnullGCPtr<Plugin> enabled_plugin() const;
 
 private:
-    MimeType(JS::Realm&, String const& type);
+    MimeType(JS::Realm&, String type);
 
     virtual JS::ThrowCompletionOr<void> initialize(JS::Realm&) override;
 
diff --git a/Userland/Libraries/LibWeb/HTML/Plugin.cpp b/Userland/Libraries/LibWeb/HTML/Plugin.cpp
index 4240a522c66..199332ef48b 100644
--- a/Userland/Libraries/LibWeb/HTML/Plugin.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Plugin.cpp
@@ -12,9 +12,9 @@
 
 namespace Web::HTML {
 
-Plugin::Plugin(JS::Realm& realm, String const& name)
+Plugin::Plugin(JS::Realm& realm, String name)
     : Bindings::LegacyPlatformObject(realm)
-    , m_name(name)
+    , m_name(move(name))
 {
 }
 
diff --git a/Userland/Libraries/LibWeb/HTML/Plugin.h b/Userland/Libraries/LibWeb/HTML/Plugin.h
index 70bed1bae89..8b145ab4a0b 100644
--- a/Userland/Libraries/LibWeb/HTML/Plugin.h
+++ b/Userland/Libraries/LibWeb/HTML/Plugin.h
@@ -25,7 +25,7 @@ public:
     JS::GCPtr<MimeType> named_item(String const& name) const;
 
 private:
-    Plugin(JS::Realm&, String const& name);
+    Plugin(JS::Realm&, String name);
 
     // https://html.spec.whatwg.org/multipage/system-state.html#concept-plugin-name
     String m_name;
diff --git a/Userland/Libraries/LibWeb/HTML/Window.cpp b/Userland/Libraries/LibWeb/HTML/Window.cpp
index 3507a81b3f0..75f5890a852 100644
--- a/Userland/Libraries/LibWeb/HTML/Window.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Window.cpp
@@ -1080,12 +1080,12 @@ Vector<JS::NonnullGCPtr<Plugin>> Window::pdf_viewer_plugin_objects()
         return {};
 
     if (m_pdf_viewer_plugin_objects.is_empty()) {
-        // FIXME: Remove the MUSTs and propagate the errors instead.
-        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), MUST(String::from_utf8("PDF Viewer"sv))).release_allocated_value_but_fixme_should_propagate_errors());
-        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), MUST(String::from_utf8("Chrome PDF Viewer"sv))).release_allocated_value_but_fixme_should_propagate_errors());
-        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), MUST(String::from_utf8("Chromium PDF Viewer"sv))).release_allocated_value_but_fixme_should_propagate_errors());
-        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), MUST(String::from_utf8("Microsoft Edge PDF Viewer"sv))).release_allocated_value_but_fixme_should_propagate_errors());
-        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), MUST(String::from_utf8("WebKit built-in PDF"sv))).release_allocated_value_but_fixme_should_propagate_errors());
+        // FIXME: Propagate errors.
+        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), "PDF Viewer"_string.release_value_but_fixme_should_propagate_errors()).release_allocated_value_but_fixme_should_propagate_errors());
+        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), "Chrome PDF Viewer"_string.release_value_but_fixme_should_propagate_errors()).release_allocated_value_but_fixme_should_propagate_errors());
+        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), "Chromium PDF Viewer"_string.release_value_but_fixme_should_propagate_errors()).release_allocated_value_but_fixme_should_propagate_errors());
+        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), "Microsoft Edge PDF Viewer"_string.release_value_but_fixme_should_propagate_errors()).release_allocated_value_but_fixme_should_propagate_errors());
+        m_pdf_viewer_plugin_objects.append(realm().heap().allocate<Plugin>(realm(), realm(), "WebKit built-in PDF"_string.release_value_but_fixme_should_propagate_errors()).release_allocated_value_but_fixme_should_propagate_errors());
     }
 
     return m_pdf_viewer_plugin_objects;