Remove Features.RustCrypto (#28582)

src/settings/Settings.tsx

@@ -90,13 +90,6 @@ export enum Features {
     NotificationSettings2 = "feature_notification_settings2",
     OidcNativeFlow = "feature_oidc_native_flow",
     ReleaseAnnouncement = "feature_release_announcement",
-
-    /** If true, use the Rust crypto implementation.
-     *
-     * This is no longer read, but we continue to populate it on all devices, to guard against people rolling back to
-     * old versions of EW that do not use rust crypto by default.
-     */
-    RustCrypto = "feature_rust_crypto",
 }
 
 export const labGroupNames: Record<LabGroup, TranslationKey> = {
@@ -469,10 +462,6 @@ export const SETTINGS: { [setting: string]: ISetting } = {
         description: _td("labs|oidc_native_flow_description"),
         default: false,
     },
-    [Features.RustCrypto]: {
-        supportedLevels: LEVELS_DEVICE_ONLY_SETTINGS,
-        default: true,
-    },
     /**
      * @deprecated in favor of {@link fontSizeDelta}
      */