E2E: Work around flakiness loading proposals

frontend/src/lib/pages/NnsProposals.svelte

@@ -128,6 +128,11 @@
     debounceFindProposals?.();
   };
 
+  // Neurons and proposals are loaded at the same time. But once neurons are
+  // loaded, proposals are loaded again. So it's possible that the component
+  // goes back into loading state immediately after proposals are loaded.
+  // TODO: Fix NnsProposals to load proposals only once and remove the
+  // work-around from NnsProposalList.page-object.ts
   $: $definedNeuronsStore, applyFilter($proposalsFiltersStore);
 
   $: $authStore.identity, (() => proposalsFiltersStore.reload())();

frontend/src/tests/page-objects/NnsProposalList.page-object.ts

@@ -88,10 +88,15 @@ export class NnsProposalListPo extends BasePageObject {
   }
 
   async waitForContentLoaded(): Promise<void> {
-    await Promise.race([
-      this.getProposalCardPo().waitFor(),
-      this.waitFor("no-proposals-msg"),
-    ]);
+    this.getSkeletonCardPo().waitForAbsent();
+    // The NnsProposals component loads neurons and proposals at the same time.
+    // But once neurons are loaded, it loads proposals again. So it's possible
+    // that the component goes back into loading state immediately after
+    // proposals are loaded.
+    // TODO: Fix NnsProposals to load proposals only once and remove the 2 lines
+    // below.
+    await new Promise((resolve) => setTimeout(resolve, 1000));
+    this.getSkeletonCardPo().waitForAbsent();
   }
 
   async getVisibleProposalIds(proposerNeuronId: string): Promise<string[]> {