---
title: Optimizely and third-party package compatibility breaking changes
slug: cms-13/docs/optimizely-third-party-packages-breaking-changes
docTags:
createdAt: 2026-07-30T20:22:06.571Z
---
This article covers known Optimizely and third-party package incompatibilities when upgrading to Content Management System (CMS 13) and provides guidance for handling them. These issues were identified during real-world upgrade testing.
:::hint{type="info"}
**Note**
This list does not cover all third-party package compatibility issues. It catalogs compatibility for commonly used packages found in real-world implementations. It may not accurately reflect third-party compatibility after CMS 13 became generally available. Refer to [https://nuget.optimizely.com/](https://nuget.optimizely.com/) for the most up-to-date compatibility.
:::
## Package compatibility summary
| Package | CMS 12 Version | CMS 13 Status | Action Required |
| ----------------------------------- | -------------- | ---------------- | ---------------------------------------------- |
| EPiServer.Find.Cms | 16.x | Not compatible | Remove; no longer supported |
| EPiServer.Forms | 5.10.x | Upgrade required | Upgrade to `EPiServer.Forms` 6.0.0 |
| EPiServer.Cms.WelcomeIntegration.UI | 2.1.x | Not compatible | Replace with `EPiServer.Cms.DamIntegration.UI` |
| Advanced.CMS.AdvancedReviews | 1.4.x | Not compatible | Remove; await update |
| Geta.NotFoundHandler.Optimizely | 6.0.x | Not compatible | Remove; await update |
| Geta.Optimizely.Sitemaps | 3.2.x | Not compatible | Remove; await update |
| Geta.Optimizely.GenericLinks | 2.0.x | Not compatible | Remove; await update |
| Geta.Optimizely.ContentTypeIcons | 2.1.x | Not compatible | Remove; await update |
| Geta.Optimizely.Categories | 1.1.x | Not compatible | Remove; await update |
| Gulla.Episerver.SqlStudio | 3.0.1 | Upgrade required | Upgrade to 3.0.2+ |
| Stott.Optimizely.RobotsHandler | Various | Not compatible | Remove; await update |
## Search & Navigation
Search & Navigation (`EPiServer.Find.Cms`) does not have a CMS 13-compatible version. Removal steps:
1. Remove `EPiServer.Find.Cms` and any Search & Navigation related packages from your `.csproj`.
2. Remove all Search & Navigation service registrations from `Startup.cs` (for example, `services.AddFind()`).
3. Remove or replace any Search & Navigation dependent code (search implementations, indexing jobs).
4. After removing Search & Navigation, you might encounter a missing `Newtonsoft.Json` reference. Add an explicit package reference: ``.
:::hint{type="info"}
**Note**
Search & Navigation removal may also require removing companion packages such as `Geta.Optimizely.Categories.Find`.
:::
## EPiServer.Forms
EPiServer.Forms (`EPiServer.Forms` 6.0.0) is compatible with CMS 13.
## EPiServer.Cms.WelcomeIntegration.UI
The Welcome Integration and DAM UI package (2.1.x) references geolocation APIs that were moved to the `EPiServer.Cms.DamIntegration.UI` package in CMS 13.
You should remove the package reference and disable `AddDAMUi()` service registration, and install `EPiServer.Cms.DamIntegration.UI` (see [Configure DAM Asset picker](docId\:TL59_p9hyGaBWt3YnCpO1)).
Replacing the package does not update DAM asset references in existing content. To update them, see [Migrate DAM from CMS 12 to CMS 13](https://docs.developers.optimizely.com/content-management-system/v13.0.0-CMS/docs/migrate-dam-from-cms-12-to-cms-13).
## Advanced.CMS.AdvancedReviews
Advanced Reviews (1.4.x) fails because it references `ServiceCollectionExtensions` types that were moved to `EPiServer.DependencyInjection`.
You should remove the package and service registration. Await an updated version.
## Geta.NotFoundHandler
`Geta.NotFoundHandler` (6.0.x) uses the `SortIndex` attribute property that was removed in CMS 13, causing a `TypeLoadException` at runtime.
You should remove the package references and service registrations. Await a CMS 13-compatible update.
## Geta.Optimizely.Sitemaps
`Geta.Optimizely.Sitemaps` (3.2.x) has access modifier conflicts with CMS 13. The `PropertySEOSitemaps` property causes a `TypeLoadException`.
You should remove the package. Await a CMS 13-compatible update. Note that configuration properties such as `SitemapOptions.EnableLanguageDropDownInAdmin` were also removed.
## Geta.Optimizely.GenericLinks
`Geta.Optimizely.GenericLinks` (2.0.x) causes a `TypeLoadException` due to `PropertyLinkDataCollection` access modifier conflicts with CMS 13's changes to `PropertyLongString`.
You should remove the package. Revert custom `LinkDataCollection` properties to standard `LinkItemCollection`. Await a CMS 13-compatible update.
## Geta.Optimizely.ContentTypeIcons
`Geta.Optimizely.ContentTypeIcons` (2.1.x) produces build errors against CMS 13.
You should remove the package reference, comment out service registrations, and remove `[ContentTypeIcon]` attributes from content type files. Await a CMS 13-compatible update.
## Geta.Optimizely.Categories
`Geta.Optimizely.Categories` (1.1.x) fails because `ContentReferenceListEditorDescriptor` constructor signatures changed in CMS 13.
You should remove the package. Removal may leave orphaned content types (`CategoryRoot`, `CategoryData`) in the database. Consider adding stub classes to prevent "could not create instance" errors, or clean up the database directly.
## Gulla.Episerver.SqlStudio
SqlStudio 3.0.1 references `ISynchronizedObjectInstanceCache` in a way that is incompatible with CMS 13.
You should upgrade to version 3.0.2 or later, which is CMS 13-compatible. Also ensure the service registration `services.AddSqlStudio()` is present. If the package is referenced, it must be registered or removed entirely.
## Stott.Optimizely.RobotsHandler
The `RobotsHandler` package references types that are incompatible with CMS 13.
You should remove the package or await an updated version. If using the package, ensure `services.AddRobotsHandler()` and `app.UseRobotsHandler()` are both present, as missing service registrations cause authorization policy errors.
## Orphaned scheduled jobs
After removing third-party packages, orphaned scheduled job registrations may remain in the database. These produce warnings at startup but are not blocking. Common orphaned jobs include those from Search & Navigation, Forms, NotFoundHandler, and Sitemaps.
You should delete orphaned job registrations within the admin UI under **Settings** > **Scheduled Jobs**, or leave them as non-blocking warnings.
## Orphaned content types
Removing packages that registered content types (such as `Geta.Optimizely.Categories`) may leave orphaned content type definitions in the database. This can cause "could not create instance" errors.
**Resolution options**:
1. Add stub classes that match the orphaned content type names to prevent instantiation errors.
2. Clean up the orphaned content types directly in the database.
3. Use the Admin UI to manage orphaned types if accessible.
## General guidance for incompatible packages
When encountering a third-party package that is not compatible with CMS 13:
1. Remove the package reference from your `.csproj` file.
2. Remove or comment out service registrations in `Startup.cs` (for example, `services.AddSomePackage()` and `app.UseSomePackage()`).
3. Remove using statements that reference the package's namespaces.
4. Remove attributes and decorators from content types that reference the package.
5. Check for transitive dependencies. Removing one package may expose missing references (such as `Newtonsoft.Json` after Search & Navigation removal).
6. Document what was removed so you can re-enable packages when CMS 13-compatible versions are available.
7. Watch for orphaned database artifacts such as scheduled jobs, content types, or database tables that remain after package removal.