deeply compare old and new params

app/web/src/helpers/cadPackages/common.ts

@@ -12,7 +12,7 @@ export const stlToGeometry = (url) =>
 
 export interface RenderArgs {
   code: State['code']
-  parameters: any
+  parameters?: RawCustomizerParams
   settings: {
     camera: State['camera']
     viewerSize: State['viewerSize']

app/web/src/helpers/cadPackages/jsCad/jsCadController.ts

@@ -129,7 +129,7 @@ export const render: DefaultKernelExport['render'] = async ({
     scriptWorker.postMessage({ action: 'init', baseURI, alias: [] })
   }
 
-  if (parameters) {
+  if (parameters && currentParameters && JSON.stringify(parameters) !== JSON.stringify(currentParameters)) {
     // we are not evaluating code, but reacting to parameters change
     scriptWorker.postMessage({
       action: 'updateParams',