fix: allow preview image uploads on plain HTTP origins

frontend/src/pages/ModelDetailPage/EditModelModal.tsx

@@ -38,6 +38,7 @@ import TagInput from "../../components/TagInput";
 import DescriptionEditor from "./DescriptionEditor";
 import { translateCategoryDisplay } from "../../utils/translateCategoryDisplay";
 import { buildCategoryTree, flattenCategoryTree } from "../../utils/categoryTree";
+import { newLocalId } from "../../utils/localId";
 
 type ImageItem =
   { kind: "existing"; id: string; url: string } | { kind: "new"; localId: string; file: File; previewUrl: string };
@@ -124,7 +125,7 @@ export default function EditModelModal({ print, onClose, onUnauthorized, onUpdat
     const newItems: ImageItem[] = Array.from(fileList).map((file) => {
       const previewUrl = URL.createObjectURL(file);
       createdUrlsRef.current.push(previewUrl);
-      return { kind: "new", localId: crypto.randomUUID(), file, previewUrl };
+      return { kind: "new", localId: newLocalId(), file, previewUrl };
     });
     setImages((prev) => [...prev, ...newItems]);
     markDirty();
@@ -152,7 +153,7 @@ export default function EditModelModal({ print, onClose, onUnauthorized, onUpdat
     if (!fileList?.length) return;
     const newItems: PlateItem[] = Array.from(fileList).map((file) => ({
       kind: "new",
-      localId: crypto.randomUUID(),
+      localId: newLocalId(),
       file,
     }));
     setPlateItems((prev) => [...prev, ...newItems]);

frontend/src/utils/gravatar.ts

@@ -1,5 +1,7 @@
 // SHA-256 works with crypto.subtle, avoiding an MD5 dependency. https://docs.gravatar.com/general/hash/
-export async function gravatarUrl(email: string, size = 128): Promise<string> {
+// crypto.subtle is missing on plain-HTTP origins; callers then fall back to initials.
+export async function gravatarUrl(email: string, size = 128): Promise<string | undefined> {
+  if (!crypto.subtle) return undefined;
   const normalized = email.trim().toLowerCase();
   const data = new TextEncoder().encode(normalized);
   const hashBuffer = await crypto.subtle.digest("SHA-256", data);

frontend/src/utils/localId.test.ts

@@ -0,0 +1,13 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { newLocalId } from "./localId";
+
+describe("newLocalId", () => {
+  afterEach(() => vi.unstubAllGlobals());
+
+  it("works without crypto.randomUUID (insecure HTTP origins)", () => {
+    vi.stubGlobal("crypto", { getRandomValues: crypto.getRandomValues.bind(crypto) });
+    const a = newLocalId();
+    expect(a).toMatch(/^[0-9a-f]{32}$/);
+    expect(newLocalId()).not.toBe(a);
+  });
+});

frontend/src/utils/localId.ts

@@ -0,0 +1,6 @@
+// crypto.randomUUID only exists in secure contexts, and self-hosted instances are often plain HTTP on a LAN.
+export function newLocalId(): string {
+  if (typeof crypto.randomUUID === "function") return crypto.randomUUID();
+  const bytes = crypto.getRandomValues(new Uint8Array(16));
+  return Array.from(bytes, (b) => b.toString(16).padStart(2, "0")).join("");
+}