diff --git a/src/lib/getKcContext/getKcContext.ts b/src/lib/getKcContext/getKcContext.ts
index 310c8c90..694da658 100644
--- a/src/lib/getKcContext/getKcContext.ts
+++ b/src/lib/getKcContext/getKcContext.ts
@@ -8,9 +8,9 @@ import { deepAssign } from "../tools/deepAssign";
 
 
 export type ExtendsKcContextBase<
-	KcContextExtended extends ({ pageId: string; } | undefined)
+	KcContextExtended extends { pageId: string; }
 	> =
-	KcContextExtended extends undefined ?
+	[KcContextExtended] extends [never] ?
 	KcContextBase :
 	AndByDiscriminatingKey<
 		"pageId",
@@ -18,7 +18,7 @@ export type ExtendsKcContextBase<
 		KcContextBase
 	>;
 
-export function getKcContext<KcContextExtended extends ({ pageId: string; } | undefined) = undefined>(
+export function getKcContext<KcContextExtended extends { pageId: string; } = never>(
 	params?: {
 		mockPageId?: ExtendsKcContextBase<KcContextExtended>["pageId"];
 		mockData?: readonly DeepPartial<ExtendsKcContextBase<KcContextExtended>>[];
@@ -51,22 +51,15 @@ export function getKcContext<KcContextExtended extends ({ pageId: string; } | un
 
 		}
 
-		const kcContext: any = { "pageId": mockPageId };
+		const kcContext: any = {};
 
 		deepAssign({
 			"target": kcContext,
-			"source": kcContextCommonMock
+			"source": kcContextDefaultMock !== undefined ?
+				kcContextDefaultMock :
+				{ "pageId": mockPageId, ...kcContextCommonMock,  }
 		});
 
-		if (kcContextDefaultMock !== undefined) {
-
-			deepAssign({
-				"target": kcContext,
-				"source": kcContextDefaultMock
-			});
-
-		}
-
 		if (partialKcContextCustomMock !== undefined) {
 
 			deepAssign({
diff --git a/src/lib/tools/deepAssign.ts b/src/lib/tools/deepAssign.ts
index 2b1bfe5b..4ac8065d 100644
--- a/src/lib/tools/deepAssign.ts
+++ b/src/lib/tools/deepAssign.ts
@@ -2,6 +2,7 @@
 import { assert } from "tsafe/assert";
 import { is } from "tsafe/is";
 
+//Warning: Be mindful that because of array this is not idempotent.
 export function deepAssign(
 	params: {
 		target: Record<string, unknown>;
diff --git a/src/test/lib/getKcContext.ts b/src/test/lib/getKcContext.ts
index 9d7020ff..2a835849 100644
--- a/src/test/lib/getKcContext.ts
+++ b/src/test/lib/getKcContext.ts
@@ -6,202 +6,245 @@ import { same } from "evt/tools/inDepth";
 import { doExtends } from "tsafe/doExtends";
 import { assert } from "tsafe/assert";
 import { kcContextMocks, kcContextCommonMock } from "../../lib/getKcContext/kcContextMocks";
-import { deepClone } from "../../lib/tools/deepClone";
+import { deepClone } from "../../lib/tools/deepClone";
 import type { Any } from "ts-toolbelt";
 
+{
 
-const authorizedMailDomains = [
-	"example.com",
-	"another-example.com",
-	"*.yet-another-example.com",
-	"*.example.com",
-	"hello-world.com"
-];
+	const authorizedMailDomains = [
+		"example.com",
+		"another-example.com",
+		"*.yet-another-example.com",
+		"*.example.com",
+		"hello-world.com"
+	];
 
-const displayName = "this is an overwritten common value";
+	const displayName = "this is an overwritten common value";
 
-const aNonStandardValue = "a non standard value";
+	const aNonStandardValue1 = "a non standard value 1";
+	const aNonStandardValue2 = "a non standard value 2";
 
-type KcContextExtended = {
-	pageId: "register.ftl";
-	authorizedMailDomains: string[];
-} | {
-	pageId: "my-extra-page-1.ftl";
-} | {
-	pageId: "my-extra-page-2.ftl";
-	aNonStandardValue: string;
-};
+	type KcContextExtended = {
+		pageId: "register.ftl";
+		authorizedMailDomains: string[];
+	} | {
+		pageId: "info.ftl";
+		aNonStandardValue1: string;
+	} | {
+		pageId: "my-extra-page-1.ftl";
+	} | {
+		pageId: "my-extra-page-2.ftl";
+		aNonStandardValue2: string;
+	};
+
+	const getKcContextProxy = (
+		params: {
+			mockPageId: ExtendsKcContextBase<KcContextExtended>["pageId"];
+		}
+	) => {
+
+		const { mockPageId } = params;
+
+		const { kcContext } = getKcContext<KcContextExtended>({
+			mockPageId,
+			"mockData": [
+				{
+					"pageId": "login.ftl",
+					"realm": { displayName }
+				},
+				{
+					"pageId": "info.ftl",
+					aNonStandardValue1
+				},
+				{
+					"pageId": "register.ftl",
+					authorizedMailDomains
+				},
+				{
+					"pageId": "my-extra-page-2.ftl",
+					aNonStandardValue2
+				}
+			]
+		});
+
+		return { kcContext };
+
+	};
+
+	{
+
+		const pageId = "login.ftl";
+
+		const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
+
+		assert(kcContext?.pageId === pageId);
+
+		doExtends<Any.Equals<typeof kcContext, KcContextBase.Login>, 1>();
+
+		assert(same(
+			//NOTE: deepClone for printIfExists or other functions...
+			deepClone(kcContext),
+			(() => {
+
+				const mock = deepClone(kcContextMocks.find(({ pageId: pageId_i }) => pageId_i === pageId)!);
+
+				mock.realm.displayName = displayName;
+
+				return mock;
+
+			})()
+		));
+
+		console.log(`PASS ${pageId}`);
 
-function getKcContextProxy(
-	params: {
-		mockPageId: ExtendsKcContextBase<KcContextExtended>["pageId"];
 	}
-) {
 
-	const { mockPageId } = params;
+	{
+		const pageId = "info.ftl";
 
-	const { kcContext } = getKcContext<KcContextExtended>({
-		mockPageId,
-		"mockData": [
-			{
-				"pageId": "login.ftl",
-				"realm": { displayName }
-			},
-			{
-				"pageId": "register.ftl",
-				authorizedMailDomains
-			},
-			{
-				"pageId": "my-extra-page-2.ftl",
-				aNonStandardValue
-			}
-		]
+		const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
+
+		assert(kcContext?.pageId === pageId);
+
+		//NOTE: I don't understand the need to add: pageId: typeof pageId; ...
+		doExtends<Any.Equals<typeof kcContext, KcContextBase.Info & { pageId: typeof pageId; aNonStandardValue1: string; }>, 1>();
+
+		assert(same(
+			deepClone(kcContext),
+			(() => {
+
+				const mock = deepClone(kcContextMocks.find(({ pageId: pageId_i }) => pageId_i === pageId)!);
+
+				Object.assign(mock, { aNonStandardValue1 });
+
+				return mock;
+
+			})()
+		));
+
+		console.log(`PASS ${pageId}`);
+
+	}
+
+	{
+		const pageId = "register.ftl";
+
+		const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
+
+		assert(kcContext?.pageId === pageId);
+
+		//NOTE: I don't understand the need to add: pageId: typeof pageId; ...
+		doExtends<Any.Equals<typeof kcContext, KcContextBase.Register & { pageId: typeof pageId; authorizedMailDomains: string[]; }>, 1>();
+
+		assert(same(
+			deepClone(kcContext),
+			(() => {
+
+				const mock = deepClone(kcContextMocks.find(({ pageId: pageId_i }) => pageId_i === pageId)!);
+
+				Object.assign(mock, { authorizedMailDomains });
+
+				return mock;
+
+			})()
+		));
+
+		console.log(`PASS ${pageId}`);
+
+	}
+
+	{
+
+		const pageId = "my-extra-page-2.ftl";
+
+		const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
+
+		assert(kcContext?.pageId === pageId);
+
+		doExtends<Any.Equals<typeof kcContext, KcContextBase.Common & { pageId: typeof pageId; aNonStandardValue2: string; }>, 1>();
+
+		kcContext.aNonStandardValue2;
+
+		assert(same(
+			deepClone(kcContext),
+			(() => {
+
+				const mock = deepClone(kcContextCommonMock);
+
+				Object.assign(mock, { pageId, aNonStandardValue2 });
+
+				return mock;
+
+			})()
+		));
+
+		console.log(`PASS ${pageId}`);
+
+	}
+
+	{
+
+		const pageId = "my-extra-page-1.ftl";
+
+		console.log("We expect a warning here =>");
+
+		const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
+
+
+		assert(kcContext?.pageId === pageId);
+
+		doExtends<Any.Equals<typeof kcContext, KcContextBase.Common & { pageId: typeof pageId;  }>, 1>();
+
+		assert(same(
+			deepClone(kcContext),
+			(() => {
+
+				const mock = deepClone(kcContextCommonMock);
+
+				Object.assign(mock, { pageId });
+
+				return mock;
+
+			})()
+		));
+
+		console.log(`PASS ${pageId}`);
+
+	}
+
+}
+
+{
+
+	const pageId = "login.ftl";
+
+	const { kcContext } = getKcContext({
+		"mockPageId": pageId
 	});
 
-	return { kcContext };
-
-}
-
-{
-
-	const pageId= "login.ftl";
-
-	const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
-
-	//@ts-expect-error
-	doExtends<Any.Equals<typeof kcContext, any>, 1>();
-
-	assert(kcContext?.pageId === pageId);
-
-	doExtends<typeof kcContext, KcContextBase.Login>();
-
-	assert(same(
-		//NOTE: deepClone for printIfExists or other functions...
-		deepClone(kcContext),
-		(() => {
-
-			const mock = deepClone(kcContextMocks.find(({ pageId: pageId_i }) => pageId_i === pageId)!);
-
-			mock.realm.displayName = displayName;
-
-			return mock;
-
-		})()
-	));
-
-	console.log(`PASS ${pageId}`);
-
-}
-
-{
-	const pageId = "register.ftl";
-
-	const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
-
-	//@ts-expect-error
-	doExtends<Any.Equals<typeof kcContext, any>, 1>();
-
-	assert(kcContext?.pageId === pageId);
-
-	doExtends<typeof kcContext, KcContextBase.Register>();
+	doExtends<Any.Equals<typeof kcContext, KcContextBase | undefined>, 1>();
 
 	assert(same(
 		deepClone(kcContext),
-		(() => {
-
-			const mock = deepClone(kcContextMocks.find(({ pageId: pageId_i }) => pageId_i === pageId)!);
-
-			Object.assign(mock, { authorizedMailDomains });
-
-			return mock;
-
-		})()
+		deepClone(kcContextMocks.find(({ pageId: pageId_i }) => pageId_i === pageId)!)
 	));
 
-	console.log(`PASS ${pageId}`);
-	
-}
-
-{
-
-	const pageId  = "my-extra-page-2.ftl";
-
-	const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
-
-	//@ts-expect-error
-	doExtends<Any.Equals<typeof kcContext, any>, 1>();
-
-	assert(kcContext?.pageId === pageId);
-
-	//@ts-expect-error
-	doExtends<typeof kcContext, KcContextBase>();
-
-	doExtends<typeof kcContext, KcContextBase.Common>();
-
-	assert(same(
-		deepClone(kcContext),
-		(() => {
-
-			const mock = deepClone(kcContextCommonMock);
-
-			Object.assign(mock, { pageId, aNonStandardValue });
-
-			return mock;
-
-		})()
-	));
-
-	console.log(`PASS ${pageId}`);
+	console.log("PASS no extension");
 
 }
 
-{
-
-	const pageId  = "my-extra-page-1.ftl";
-
-	console.log("We expect a warning here =>");
-
-	const { kcContext } = getKcContextProxy({ "mockPageId": pageId });
-
-	//@ts-expect-error
-	doExtends<Any.Equals<typeof kcContext, any>, 1>();
-
-	assert(kcContext?.pageId === pageId);
-
-	//@ts-expect-error
-	doExtends<typeof kcContext, KcContextBase>();
-
-	doExtends<typeof kcContext, KcContextBase.Common>();
-
-	assert(same(
-		deepClone(kcContext),
-		(() => {
-
-			const mock = deepClone(kcContextCommonMock);
-
-			Object.assign(mock, { pageId });
-
-			return mock;
-
-		})()
-	));
-
-	console.log(`PASS ${pageId}`);
-
-}
 
 {
+
 	const { kcContext } = getKcContext();
 
-	//@ts-expect-error
-	doExtends<Any.Equals<typeof kcContext, any>, 1>();
+	doExtends<Any.Equals<typeof kcContext, KcContextBase | undefined>, 1>();
 
-	doExtends<typeof kcContext, KcContextBase | undefined>();
+	assert(kcContext === undefined);
+
+	console.log("PASS no extension, no mock");
 
 }
 
 
 
-
-
-