fix: toggle flag (#3480)

frontend/common/providers/FeatureListProvider.js

@@ -51,15 +51,26 @@ const FeatureListProvider = class extends React.Component {
     this.editFeatureValue(
       projectId,
       environmentId,
+      /* todo: Saving features involves sending an adjusted project flag rather than a feature state (old tech debt).
+       This will be removed when migrating to RTK. The following converts the feature state to the accepted format.
+      */
       {
         ...projectFlag,
         default_enabled: !environmentFlag.enabled,
+        initial_value: environmentFlag.feature_state_value,
+        multivariate_options: projectFlag.multivariate_options.map((mv) => {
+          const matching =
+            environmentFlag.multivariate_feature_state_values.find(
+              (v) => v.multivariate_feature_option == mv.id,
+            )
+          return {
+            ...mv,
+            default_percentage_allocation: matching.percentage_allocation,
+          }
+        }),
       },
       projectFlag,
-      {
-        ...environmentFlag,
-        enabled: !environmentFlag.enabled,
-      },
+      environmentFlag,
     )
   }