refactor(plugins): remove non-functional experimental manifest option (#5821)

The `experimental.threads` manifest option never actually worked, so drop
it from the schema, the generated types, the loader and the docs.

plugins/README.md

@@ -136,7 +136,7 @@ Every plugin must include a `manifest.json` file. Example:
 
 **Required fields:** `name`, `author`, `version`
 
-**Optional fields:** `description`, `website`, `config`, `permissions`, `experimental`
+**Optional fields:** `description`, `website`, `config`, `permissions`
 
 #### Config Definition
 
@@ -160,24 +160,6 @@ The `config` field defines the plugin's configuration schema using [JSON Schema
 }
 ```
 
-#### Experimental Features
-
-Plugins can opt-in to experimental WebAssembly features that may change or be removed in future versions. Currently supported:
-
-- **`threads`** – Enables WebAssembly threads support (for plugins compiled with multi-threading)
-
-```json
-{
-  "experimental": {
-    "threads": {
-      "reason": "Required for concurrent audio processing"
-    }
-  }
-}
-```
-
-> **Note:** Experimental features may have compatibility or performance implications. Use only when necessary.
-
 ---
 
 ## Capabilities

plugins/manager_loader.go

@@ -13,8 +13,6 @@ import (
 	"github.com/navidrome/navidrome/plugins/host"
 	"github.com/navidrome/navidrome/scheduler"
 	"github.com/tetratelabs/wazero"
-	"github.com/tetratelabs/wazero/api"
-	"github.com/tetratelabs/wazero/experimental"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -377,12 +375,6 @@ func (m *Manager) loadPluginWithConfig(p *model.Plugin) error {
 		WithCompilationCache(m.cache).
 		WithCloseOnContextDone(true)
 
-	// Enable experimental threads if requested in manifest
-	if pkg.Manifest.HasExperimentalThreads() {
-		runtimeConfig = runtimeConfig.WithCoreFeatures(api.CoreFeaturesV2 | experimental.CoreFeaturesThreads)
-		log.Debug(ctx, "Enabling experimental threads support")
-	}
-
 	extismConfig := extism.PluginConfig{
 		EnableWasi:                true,
 		RuntimeConfig:             runtimeConfig,

plugins/manifest-schema.json

@@ -34,9 +34,6 @@
     "permissions": {
       "$ref": "#/$defs/Permissions"
     },
-    "experimental": {
-      "$ref": "#/$defs/Experimental"
-    },
     "config": {
       "$ref": "#/$defs/ConfigDefinition"
     }
@@ -58,27 +55,6 @@
         }
       }
     },
-    "Experimental": {
-      "type": "object",
-      "description": "Experimental features that may change or be removed in future versions",
-      "additionalProperties": false,
-      "properties": {
-        "threads": {
-          "$ref": "#/$defs/ThreadsFeature"
-        }
-      }
-    },
-    "ThreadsFeature": {
-      "type": "object",
-      "description": "Enable experimental WebAssembly threads support",
-      "additionalProperties": false,
-      "properties": {
-        "reason": {
-          "type": "string",
-          "description": "Explanation for why threads support is needed"
-        }
-      }
-    },
     "Permissions": {
       "type": "object",
       "description": "Permissions required by the plugin",

plugins/manifest.go

@@ -117,11 +117,6 @@ func ValidateWithCapabilities(m *Manifest, capabilities []Capability) error {
 	return nil
 }
 
-// HasExperimentalThreads returns true if the manifest requests experimental threads support.
-func (m *Manifest) HasExperimentalThreads() bool {
-	return m.Experimental != nil && m.Experimental.Threads != nil
-}
-
 // HasLibraryFilesystemPermission checks if the manifest grants filesystem permission for libraries.
 func (m *Manifest) HasLibraryFilesystemPermission() bool {
 	return m.Permissions != nil &&

plugins/manifest_gen.go

@@ -45,12 +45,6 @@ func (j *ConfigDefinition) UnmarshalJSON(value []byte) error {
 	return nil
 }
 
-// Experimental features that may change or be removed in future versions
-type Experimental struct {
-	// Threads corresponds to the JSON schema field "threads".
-	Threads *ThreadsFeature `json:"threads,omitempty" yaml:"threads,omitempty" mapstructure:"threads,omitempty"`
-}
-
 // HTTP access permissions for a plugin
 type HTTPPermission struct {
 	// Explanation for why HTTP access is needed
@@ -109,9 +103,6 @@ type Manifest struct {
 	// A brief description of what the plugin does
 	Description *string `json:"description,omitempty" yaml:"description,omitempty" mapstructure:"description,omitempty"`
 
-	// Experimental corresponds to the JSON schema field "experimental".
-	Experimental *Experimental `json:"experimental,omitempty" yaml:"experimental,omitempty" mapstructure:"experimental,omitempty"`
-
 	// The display name of the plugin
 	Name string `json:"name" yaml:"name" mapstructure:"name"`
 
@@ -242,12 +233,6 @@ func (j *TaskQueuePermission) UnmarshalJSON(value []byte) error {
 	return nil
 }
 
-// Enable experimental WebAssembly threads support
-type ThreadsFeature struct {
-	// Explanation for why threads support is needed
-	Reason *string `json:"reason,omitempty" yaml:"reason,omitempty" mapstructure:"reason,omitempty"`
-}
-
 // Users service permissions for accessing user information
 type UsersPermission struct {
 	// Explanation for why users access is needed

plugins/manifest_test.go

@@ -117,76 +117,6 @@ var _ = Describe("Manifest", func() {
 		})
 	})
 
-	Describe("HasExperimentalThreads", func() {
-		It("returns false when no experimental section", func() {
-			m := &Manifest{}
-			Expect(m.HasExperimentalThreads()).To(BeFalse())
-		})
-
-		It("returns false when experimental section has no threads", func() {
-			m := &Manifest{
-				Experimental: &Experimental{},
-			}
-			Expect(m.HasExperimentalThreads()).To(BeFalse())
-		})
-
-		It("returns true when threads feature is present", func() {
-			m := &Manifest{
-				Experimental: &Experimental{
-					Threads: &ThreadsFeature{},
-				},
-			}
-			Expect(m.HasExperimentalThreads()).To(BeTrue())
-		})
-
-		It("returns true when threads feature has a reason", func() {
-			m := &Manifest{
-				Experimental: &Experimental{
-					Threads: &ThreadsFeature{
-						Reason: new("Required for concurrent processing"),
-					},
-				},
-			}
-			Expect(m.HasExperimentalThreads()).To(BeTrue())
-		})
-
-		It("parses experimental.threads from JSON", func() {
-			data := []byte(`{
-				"name": "Threaded Plugin",
-				"author": "Test Author",
-				"version": "1.0.0",
-				"experimental": {
-					"threads": {
-						"reason": "To use multi-threaded WASM module"
-					}
-				}
-			}`)
-
-			var m Manifest
-			err := json.Unmarshal(data, &m)
-			Expect(err).ToNot(HaveOccurred())
-			Expect(m.HasExperimentalThreads()).To(BeTrue())
-			Expect(m.Experimental.Threads.Reason).ToNot(BeNil())
-			Expect(*m.Experimental.Threads.Reason).To(Equal("To use multi-threaded WASM module"))
-		})
-
-		It("parses experimental.threads without reason from JSON", func() {
-			data := []byte(`{
-				"name": "Threaded Plugin",
-				"author": "Test Author",
-				"version": "1.0.0",
-				"experimental": {
-					"threads": {}
-				}
-			}`)
-
-			var m Manifest
-			err := json.Unmarshal(data, &m)
-			Expect(err).ToNot(HaveOccurred())
-			Expect(m.HasExperimentalThreads()).To(BeTrue())
-		})
-	})
-
 	Describe("ParseManifest", func() {
 		It("parses a valid manifest with users permission", func() {
 			data := []byte(`{