Index: frontend/node_modules/internal-slot/index.d.ts
===================================================================
--- frontend/node_modules/internal-slot/index.d.ts	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
+++ frontend/node_modules/internal-slot/index.d.ts	(revision 9af201e94b5a79beb92a30858fc54de4bc3b9449)
@@ -0,0 +1,12 @@
+declare namespace SLOT {
+	type InternalSlot = string; // `[[${string}]]`; // TODO: restrict this to require the brackets
+}
+
+declare const SLOT: {
+	assert(O: object, slot: SLOT.InternalSlot): void;
+	get(O: object, slot: SLOT.InternalSlot): unknown;
+	set(O: object, slot: SLOT.InternalSlot, value?: unknown): void;
+	has(O: object, slot: SLOT.InternalSlot): boolean;
+}
+
+export = SLOT;