diff --git a/Userland/Applications/PixelPaint/Image.cpp b/Userland/Applications/PixelPaint/Image.cpp
index c95c717401..86c691035d 100644
--- a/Userland/Applications/PixelPaint/Image.cpp
+++ b/Userland/Applications/PixelPaint/Image.cpp
@@ -121,31 +121,32 @@ ErrorOr<NonnullRefPtr<Image>> Image::try_create_from_pixel_paint_json(JsonObject
     return image;
 }
 
-void Image::serialize_as_json(JsonObjectSerializer<StringBuilder>& json) const
+ErrorOr<void> Image::serialize_as_json(JsonObjectSerializer<StringBuilder>& json) const
 {
-    MUST(json.add("width"sv, m_size.width()));
-    MUST(json.add("height"sv, m_size.height()));
+    TRY(json.add("width"sv, m_size.width()));
+    TRY(json.add("height"sv, m_size.height()));
     {
-        auto json_layers = MUST(json.add_array("layers"sv));
+        auto json_layers = TRY(json.add_array("layers"sv));
         for (auto const& layer : m_layers) {
             Gfx::BMPWriter bmp_writer;
-            auto json_layer = MUST(json_layers.add_object());
-            MUST(json_layer.add("width"sv, layer.size().width()));
-            MUST(json_layer.add("height"sv, layer.size().height()));
-            MUST(json_layer.add("name"sv, layer.name()));
-            MUST(json_layer.add("locationx"sv, layer.location().x()));
-            MUST(json_layer.add("locationy"sv, layer.location().y()));
-            MUST(json_layer.add("opacity_percent"sv, layer.opacity_percent()));
-            MUST(json_layer.add("visible"sv, layer.is_visible()));
-            MUST(json_layer.add("selected"sv, layer.is_selected()));
-            MUST(json_layer.add("bitmap"sv, encode_base64(bmp_writer.dump(layer.content_bitmap()))));
+            auto json_layer = TRY(json_layers.add_object());
+            TRY(json_layer.add("width"sv, layer.size().width()));
+            TRY(json_layer.add("height"sv, layer.size().height()));
+            TRY(json_layer.add("name"sv, layer.name()));
+            TRY(json_layer.add("locationx"sv, layer.location().x()));
+            TRY(json_layer.add("locationy"sv, layer.location().y()));
+            TRY(json_layer.add("opacity_percent"sv, layer.opacity_percent()));
+            TRY(json_layer.add("visible"sv, layer.is_visible()));
+            TRY(json_layer.add("selected"sv, layer.is_selected()));
+            TRY(json_layer.add("bitmap"sv, encode_base64(bmp_writer.dump(layer.content_bitmap()))));
             if (layer.is_masked())
-                MUST(json_layer.add("mask"sv, encode_base64(bmp_writer.dump(*layer.mask_bitmap()))));
-            MUST(json_layer.finish());
+                TRY(json_layer.add("mask"sv, encode_base64(bmp_writer.dump(*layer.mask_bitmap()))));
+            TRY(json_layer.finish());
         }
 
-        MUST(json_layers.finish());
+        TRY(json_layers.finish());
     }
+    return {};
 }
 
 ErrorOr<NonnullRefPtr<Gfx::Bitmap>> Image::try_compose_bitmap(Gfx::BitmapFormat format) const
diff --git a/Userland/Applications/PixelPaint/Image.h b/Userland/Applications/PixelPaint/Image.h
index 3ad98ba468..ef66374698 100644
--- a/Userland/Applications/PixelPaint/Image.h
+++ b/Userland/Applications/PixelPaint/Image.h
@@ -72,7 +72,7 @@ public:
 
     void paint_into(GUI::Painter&, Gfx::IntRect const& dest_rect) const;
 
-    void serialize_as_json(JsonObjectSerializer<StringBuilder>& json) const;
+    ErrorOr<void> serialize_as_json(JsonObjectSerializer<StringBuilder>& json) const;
     ErrorOr<void> export_bmp_to_file(Core::File&, bool preserve_alpha_channel);
     ErrorOr<void> export_png_to_file(Core::File&, bool preserve_alpha_channel);
     ErrorOr<void> export_qoi_to_file(Core::File&) const;
diff --git a/Userland/Applications/PixelPaint/ImageEditor.cpp b/Userland/Applications/PixelPaint/ImageEditor.cpp
index 66f56ec9d8..afcedbef02 100644
--- a/Userland/Applications/PixelPaint/ImageEditor.cpp
+++ b/Userland/Applications/PixelPaint/ImageEditor.cpp
@@ -733,26 +733,26 @@ void ImageEditor::save_project_as()
     set_unmodified();
 }
 
-Result<void, DeprecatedString> ImageEditor::save_project_to_file(Core::File& file) const
+ErrorOr<void> ImageEditor::save_project_to_file(Core::File& file) const
 {
     StringBuilder builder;
-    auto json = MUST(JsonObjectSerializer<>::try_create(builder));
-    m_image->serialize_as_json(json);
-    auto json_guides = MUST(json.add_array("guides"sv));
+    auto json = TRY(JsonObjectSerializer<>::try_create(builder));
+    TRY(m_image->serialize_as_json(json));
+    auto json_guides = TRY(json.add_array("guides"sv));
     for (auto const& guide : m_guides) {
-        auto json_guide = MUST(json_guides.add_object());
-        MUST(json_guide.add("offset"sv, (double)guide.offset()));
+        auto json_guide = TRY(json_guides.add_object());
+        TRY(json_guide.add("offset"sv, (double)guide.offset()));
         if (guide.orientation() == Guide::Orientation::Vertical)
-            MUST(json_guide.add("orientation"sv, "vertical"));
+            TRY(json_guide.add("orientation"sv, "vertical"));
         else if (guide.orientation() == Guide::Orientation::Horizontal)
-            MUST(json_guide.add("orientation"sv, "horizontal"));
-        MUST(json_guide.finish());
+            TRY(json_guide.add("orientation"sv, "horizontal"));
+        TRY(json_guide.finish());
     }
-    MUST(json_guides.finish());
-    MUST(json.finish());
+    TRY(json_guides.finish());
+    TRY(json.finish());
 
     if (!file.write(builder.string_view()))
-        return DeprecatedString { file.error_string() };
+        return Error::from_errno(file.error());
     return {};
 }
 
diff --git a/Userland/Applications/PixelPaint/ImageEditor.h b/Userland/Applications/PixelPaint/ImageEditor.h
index 391b2f0b43..92480d283a 100644
--- a/Userland/Applications/PixelPaint/ImageEditor.h
+++ b/Userland/Applications/PixelPaint/ImageEditor.h
@@ -148,7 +148,7 @@ private:
     GUI::MouseEvent event_adjusted_for_layer(GUI::MouseEvent const&, Layer const&) const;
     GUI::MouseEvent event_with_pan_and_scale_applied(GUI::MouseEvent const&) const;
 
-    Result<void, DeprecatedString> save_project_to_file(Core::File&) const;
+    ErrorOr<void> save_project_to_file(Core::File&) const;
 
     int calculate_ruler_step_size() const;
     Gfx::IntRect mouse_indicator_rect_x() const;