diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp
index 41d4ab9883..04539e2f88 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/Duration.cpp
@@ -438,12 +438,13 @@ ThrowCompletionOr<double> calculate_offset_shift(VM& vm, Value relative_to_value
         return 0.0;
 
     auto& relative_to = static_cast<ZonedDateTime&>(relative_to_value.as_object());
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { relative_to.time_zone() }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
 
     // 2. Let instant be ! CreateTemporalInstant(relativeTo.[[Nanoseconds]]).
     auto* instant = MUST(create_temporal_instant(vm, relative_to.nanoseconds()));
 
     // 3. Let offsetBefore be ? GetOffsetNanosecondsFor(relativeTo.[[TimeZone]], instant).
-    auto offset_before = TRY(get_offset_nanoseconds_for(vm, &relative_to.time_zone(), *instant));
+    auto offset_before = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *instant));
 
     // 4. Let after be ? AddZonedDateTime(relativeTo.[[Nanoseconds]], relativeTo.[[TimeZone]], relativeTo.[[Calendar]], y, mon, w, d, 0, 0, 0, 0, 0, 0).
     auto* after = TRY(add_zoned_date_time(vm, relative_to.nanoseconds(), &relative_to.time_zone(), relative_to.calendar(), years, months, weeks, days, 0, 0, 0, 0, 0, 0));
@@ -452,7 +453,7 @@ ThrowCompletionOr<double> calculate_offset_shift(VM& vm, Value relative_to_value
     auto* instant_after = MUST(create_temporal_instant(vm, *after));
 
     // 6. Let offsetAfter be ? GetOffsetNanosecondsFor(relativeTo.[[TimeZone]], instantAfter).
-    auto offset_after = TRY(get_offset_nanoseconds_for(vm, &relative_to.time_zone(), *instant_after));
+    auto offset_after = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *instant_after));
 
     // 7. Return offsetAfter - offsetBefore.
     return offset_after - offset_before;
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/Instant.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/Instant.cpp
index b064957f7b..98ffe99689 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/Instant.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/Instant.cpp
@@ -300,8 +300,10 @@ ThrowCompletionOr<String> temporal_instant_to_string(VM& vm, Instant& instant, V
     }
     // 9. Else,
     else {
+        auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
+
         // a. Let offsetNs be ? GetOffsetNanosecondsFor(timeZone, instant).
-        auto offset_ns = TRY(get_offset_nanoseconds_for(vm, time_zone, instant));
+        auto offset_ns = TRY(get_offset_nanoseconds_for(vm, time_zone_record, instant));
 
         // b. Let timeZoneString be ! FormatISOTimeZoneOffsetString(offsetNs).
         time_zone_string = MUST_OR_THROW_OOM(format_iso_time_zone_offset_string(vm, offset_ns));
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.cpp
index fc16472ea3..89b9bf8e9b 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.cpp
@@ -329,14 +329,15 @@ ThrowCompletionOr<Object*> to_temporal_time_zone(VM& vm, Value temporal_time_zon
     return MUST_OR_THROW_OOM(create_temporal_time_zone(vm, *parse_result.offset_string));
 }
 
-// 11.6.8 GetOffsetNanosecondsFor ( timeZone, instant ), https://tc39.es/proposal-temporal/#sec-temporal-getoffsetnanosecondsfor
-ThrowCompletionOr<double> get_offset_nanoseconds_for(VM& vm, Value time_zone, Instant& instant)
+// 11.5.19 GetOffsetNanosecondsFor ( timeZoneRec, instant ), https://tc39.es/proposal-temporal/#sec-temporal-getoffsetnanosecondsfor
+ThrowCompletionOr<double> get_offset_nanoseconds_for(VM& vm, TimeZoneMethods const& time_zone_record, Instant const& instant)
 {
-    // 1. Let getOffsetNanosecondsFor be ? GetMethod(timeZone, "getOffsetNanosecondsFor").
-    auto get_offset_nanoseconds_for = TRY(time_zone.get_method(vm, vm.names.getOffsetNanosecondsFor));
+    // 1. Let offsetNanoseconds be ? TimeZoneMethodsRecordCall(timeZoneRec, GET-OFFSET-NANOSECONDS-FOR, « instant »).
+    auto offset_nanoseconds_value = TRY(time_zone_methods_record_call(vm, time_zone_record, TimeZoneMethod::GetOffsetNanosecondsFor, { { &instant } }));
 
-    // 2. Let offsetNanoseconds be ? Call(getOffsetNanosecondsFor, timeZone, « instant »).
-    auto offset_nanoseconds_value = TRY(call(vm, get_offset_nanoseconds_for, time_zone, &instant));
+    // 2. If TimeZoneMethodsRecordIsBuiltin(timeZoneRec), return ℝ(offsetNanoseconds).
+    if (time_zone_methods_record_is_builtin(time_zone_record))
+        return offset_nanoseconds_value.as_double();
 
     // 3. If Type(offsetNanoseconds) is not Number, throw a TypeError exception.
     if (!offset_nanoseconds_value.is_number())
@@ -360,8 +361,10 @@ ThrowCompletionOr<double> get_offset_nanoseconds_for(VM& vm, Value time_zone, In
 // 11.6.9 BuiltinTimeZoneGetOffsetStringFor ( timeZone, instant ), https://tc39.es/proposal-temporal/#sec-temporal-builtintimezonegetoffsetstringfor
 ThrowCompletionOr<String> builtin_time_zone_get_offset_string_for(VM& vm, Value time_zone, Instant& instant)
 {
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
+
     // 1. Let offsetNanoseconds be ? GetOffsetNanosecondsFor(timeZone, instant).
-    auto offset_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone, instant));
+    auto offset_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone_record, instant));
 
     // 2. Return ! FormatTimeZoneOffsetString(offsetNanoseconds).
     return MUST_OR_THROW_OOM(format_time_zone_offset_string(vm, offset_nanoseconds));
@@ -370,10 +373,12 @@ ThrowCompletionOr<String> builtin_time_zone_get_offset_string_for(VM& vm, Value
 // 11.6.10 BuiltinTimeZoneGetPlainDateTimeFor ( timeZone, instant, calendar ), https://tc39.es/proposal-temporal/#sec-temporal-builtintimezonegetplaindatetimefor
 ThrowCompletionOr<PlainDateTime*> builtin_time_zone_get_plain_date_time_for(VM& vm, Value time_zone, Instant& instant, Object& calendar)
 {
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
+
     // 1. Assert: instant has an [[InitializedTemporalInstant]] internal slot.
 
     // 2. Let offsetNanoseconds be ? GetOffsetNanosecondsFor(timeZone, instant).
-    auto offset_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone, instant));
+    auto offset_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone_record, instant));
 
     // 3. Let result be ! GetISOPartsFromEpoch(ℝ(instant.[[Nanoseconds]])).
     auto result = get_iso_parts_from_epoch(vm, instant.nanoseconds().big_integer());
@@ -465,17 +470,17 @@ ThrowCompletionOr<NonnullGCPtr<Instant>> disambiguate_possible_instants(VM& vm,
     // 13. Let dayAfter be ! CreateTemporalInstant(dayAfterNs).
     auto* day_after = MUST(create_temporal_instant(vm, day_after_ns));
 
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetOffsetNanosecondsFor, TimeZoneMethod::GetPossibleInstantsFor } }));
+
     // 14. Let offsetBefore be ? GetOffsetNanosecondsFor(timeZone, dayBefore).
-    auto offset_before = TRY(get_offset_nanoseconds_for(vm, time_zone, *day_before));
+    auto offset_before = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *day_before));
 
     // 15. Let offsetAfter be ? GetOffsetNanosecondsFor(timeZone, dayAfter).
-    auto offset_after = TRY(get_offset_nanoseconds_for(vm, time_zone, *day_after));
+    auto offset_after = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *day_after));
 
     // 16. Let nanoseconds be offsetAfter - offsetBefore.
     auto nanoseconds = offset_after - offset_before;
 
-    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetPossibleInstantsFor } }));
-
     // 17. If disambiguation is "earlier", then
     if (disambiguation == "earlier"sv) {
         // a. Let earlier be ? AddDateTime(dateTime.[[ISOYear]], dateTime.[[ISOMonth]], dateTime.[[ISODay]], dateTime.[[ISOHour]], dateTime.[[ISOMinute]], dateTime.[[ISOSecond]], dateTime.[[ISOMillisecond]], dateTime.[[ISOMicrosecond]], dateTime.[[ISONanosecond]], dateTime.[[Calendar]], 0, 0, 0, 0, 0, 0, 0, 0, 0, -nanoseconds, undefined).
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.h b/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.h
index cc530e0515..290e3593fe 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.h
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/TimeZone.h
@@ -46,7 +46,7 @@ BigInt* get_named_time_zone_previous_transition(VM&, StringView time_zone_identi
 ThrowCompletionOr<String> format_time_zone_offset_string(VM&, double offset_nanoseconds);
 ThrowCompletionOr<String> format_iso_time_zone_offset_string(VM&, double offset_nanoseconds);
 ThrowCompletionOr<Object*> to_temporal_time_zone(VM&, Value temporal_time_zone_like);
-ThrowCompletionOr<double> get_offset_nanoseconds_for(VM&, Value time_zone, Instant&);
+ThrowCompletionOr<double> get_offset_nanoseconds_for(VM& vm, TimeZoneMethods const& time_zone_record, Instant const& instant);
 ThrowCompletionOr<String> builtin_time_zone_get_offset_string_for(VM&, Value time_zone, Instant&);
 ThrowCompletionOr<PlainDateTime*> builtin_time_zone_get_plain_date_time_for(VM&, Value time_zone, Instant&, Object& calendar);
 ThrowCompletionOr<NonnullGCPtr<Instant>> builtin_time_zone_get_instant_for(VM&, Value time_zone, PlainDateTime&, StringView disambiguation);
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp
index 2f9919bb47..908121ab6a 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTime.cpp
@@ -81,13 +81,13 @@ ThrowCompletionOr<BigInt const*> interpret_iso_date_time_offset(VM& vm, i32 year
     VERIFY(offset_option.is_one_of("prefer"sv, "reject"sv));
 
     // 7. Let possibleInstants be ? GetPossibleInstantsFor(timeZone, dateTime).
-    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetPossibleInstantsFor } }));
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone.as_object() }, { { TimeZoneMethod::GetPossibleInstantsFor, TimeZoneMethod::GetOffsetNanosecondsFor } }));
     auto possible_instants = TRY(get_possible_instants_for(vm, time_zone_record, *date_time));
 
     // 8. For each element candidate of possibleInstants, do
     for (auto candidate : possible_instants) {
         // a. Let candidateNanoseconds be ? GetOffsetNanosecondsFor(timeZone, candidate).
-        auto candidate_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone, *candidate));
+        auto candidate_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *candidate));
 
         // b. If candidateNanoseconds = offsetNanoseconds, then
         if (candidate_nanoseconds == offset_nanoseconds) {
@@ -329,8 +329,10 @@ ThrowCompletionOr<String> temporal_zoned_date_time_to_string(VM& vm, ZonedDateTi
     }
     // 11. Else,
     else {
+        auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
+
         // a. Let offsetNs be ? GetOffsetNanosecondsFor(timeZone, instant).
-        auto offset_ns = TRY(get_offset_nanoseconds_for(vm, &time_zone, *instant));
+        auto offset_ns = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *instant));
 
         // b. Let offsetString be ! FormatISOTimeZoneOffsetString(offsetNs).
         offset_string = MUST_OR_THROW_OOM(format_iso_time_zone_offset_string(vm, offset_ns));
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTimePrototype.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTimePrototype.cpp
index fb5bed0e70..9f8e21374d 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTimePrototype.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/ZonedDateTimePrototype.cpp
@@ -674,13 +674,14 @@ JS_DEFINE_NATIVE_FUNCTION(ZonedDateTimePrototype::offset_nanoseconds_getter)
     auto zoned_date_time = TRY(typed_this_object(vm));
 
     // 3. Let timeZone be zonedDateTime.[[TimeZone]].
-    auto& time_zone = zoned_date_time->time_zone();
+    // 3. Let timeZoneRec be ? CreateTimeZoneMethodsRecord(zonedDateTime.[[TimeZone]], « GET-OFFSET-NANOSECONDS-FOR »).
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { zoned_date_time->time_zone() }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
 
     // 4. Let instant be ! CreateTemporalInstant(zonedDateTime.[[Nanoseconds]]).
     auto* instant = MUST(create_temporal_instant(vm, zoned_date_time->nanoseconds()));
 
-    // 5. Return 𝔽(? GetOffsetNanosecondsFor(timeZone, instant)).
-    return Value(TRY(get_offset_nanoseconds_for(vm, &time_zone, *instant)));
+    // 5. Return 𝔽(? GetOffsetNanosecondsFor(timeZoneRec, instant)).
+    return Value(TRY(get_offset_nanoseconds_for(vm, time_zone_record, *instant)));
 }
 
 // 6.3.30 get Temporal.ZonedDateTime.prototype.offset, https://tc39.es/proposal-temporal/#sec-get-temporal.zoneddatetime.prototype.offset
@@ -1025,6 +1026,8 @@ JS_DEFINE_NATIVE_FUNCTION(ZonedDateTimePrototype::round)
     // 9. Let timeZone be zonedDateTime.[[TimeZone]].
     auto& time_zone = zoned_date_time->time_zone();
 
+    auto time_zone_record = TRY(create_time_zone_methods_record(vm, NonnullGCPtr<Object> { time_zone }, { { TimeZoneMethod::GetOffsetNanosecondsFor } }));
+
     // 10. Let instant be ! CreateTemporalInstant(zonedDateTime.[[Nanoseconds]]).
     auto* instant = MUST(create_temporal_instant(vm, zoned_date_time->nanoseconds()));
 
@@ -1062,7 +1065,7 @@ JS_DEFINE_NATIVE_FUNCTION(ZonedDateTimePrototype::round)
     auto round_result = round_iso_date_time(temporal_date_time->iso_year(), temporal_date_time->iso_month(), temporal_date_time->iso_day(), temporal_date_time->iso_hour(), temporal_date_time->iso_minute(), temporal_date_time->iso_second(), temporal_date_time->iso_millisecond(), temporal_date_time->iso_microsecond(), temporal_date_time->iso_nanosecond(), rounding_increment, *smallest_unit, rounding_mode, day_length_ns);
 
     // 21. Let offsetNanoseconds be ? GetOffsetNanosecondsFor(timeZone, instant).
-    auto offset_nanoseconds = TRY(get_offset_nanoseconds_for(vm, &time_zone, *instant));
+    auto offset_nanoseconds = TRY(get_offset_nanoseconds_for(vm, time_zone_record, *instant));
 
     // 22. Let epochNanoseconds be ? InterpretISODateTimeOffset(roundResult.[[Year]], roundResult.[[Month]], roundResult.[[Day]], roundResult.[[Hour]], roundResult.[[Minute]], roundResult.[[Second]], roundResult.[[Millisecond]], roundResult.[[Microsecond]], roundResult.[[Nanosecond]], option, offsetNanoseconds, timeZone, "compatible", "prefer", match exactly).
     auto* epoch_nanoseconds = TRY(interpret_iso_date_time_offset(vm, round_result.year, round_result.month, round_result.day, round_result.hour, round_result.minute, round_result.second, round_result.millisecond, round_result.microsecond, round_result.nanosecond, OffsetBehavior::Option, offset_nanoseconds, &time_zone, "compatible"sv, "prefer"sv, MatchBehavior::MatchExactly));
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Instant/Instant.prototype.toString.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Instant/Instant.prototype.toString.js
index 6f482e7a85..d730f6a796 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Instant/Instant.prototype.toString.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Instant/Instant.prototype.toString.js
@@ -67,6 +67,6 @@ describe("errors", () => {
         const instant = new Temporal.Instant(0n);
         expect(() => {
             instant.toString({ timeZone: {} });
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDate.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDate.js
index d6680316f9..dc61a5f05c 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDate.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDate.js
@@ -55,6 +55,6 @@ describe("errors", () => {
     test("custom time zone doesn't have a getOffsetNanosecondsFor function", () => {
         expect(() => {
             Temporal.Now.plainDate({}, {});
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateISO.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateISO.js
index 094f41cb67..0505b7d1a2 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateISO.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateISO.js
@@ -52,6 +52,6 @@ describe("errors", () => {
     test("custom time zone doesn't have a getOffsetNanosecondsFor function", () => {
         expect(() => {
             Temporal.Now.plainDateISO({});
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js
index 1675371cdc..0aaf7e99c0 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTime.js
@@ -104,6 +104,6 @@ describe("errors", () => {
     test("custom time zone doesn't have a getOffsetNanosecondsFor function", () => {
         expect(() => {
             Temporal.Now.plainDateTime({}, {});
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTimeISO.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTimeISO.js
index af133cee11..14f12749b4 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTimeISO.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainDateTimeISO.js
@@ -94,6 +94,6 @@ describe("errors", () => {
     test("custom time zone doesn't have a getOffsetNanosecondsFor function", () => {
         expect(() => {
             Temporal.Now.plainDateTimeISO({});
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainTimeISO.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainTimeISO.js
index 993e6f6bf0..d7a27dbbb7 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainTimeISO.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Now/Now.plainTimeISO.js
@@ -39,6 +39,6 @@ describe("errors", () => {
     test("custom time zone doesn't have a getOffsetNanosecondsFor function", () => {
         expect(() => {
             Temporal.Now.plainTimeISO({});
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.from.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.from.js
index b8de3c2a1c..702b038c47 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.from.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDate/PlainDate.from.js
@@ -41,7 +41,7 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             Temporal.PlainDate.from(zonedDateTime);
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 
     test("invalid date time string", () => {
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDateTime/PlainDateTime.from.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDateTime/PlainDateTime.from.js
index 371c9b7a01..0b70105a51 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDateTime/PlainDateTime.from.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainDateTime/PlainDateTime.from.js
@@ -175,7 +175,7 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             Temporal.PlainDateTime.from(zonedDateTime);
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 
     test("string must not contain a UTC designator", () => {
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.from.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.from.js
index 9ff8e384ee..c88206ebc5 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.from.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.from.js
@@ -53,7 +53,7 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             Temporal.PlainTime.from(zonedDateTime);
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 
     test("string must not contain a UTC designator", () => {
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/TimeZone/TimeZone.prototype.getPlainDateTimeFor.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/TimeZone/TimeZone.prototype.getPlainDateTimeFor.js
index 5ca0d5d7b7..aaa2c11a0b 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/TimeZone/TimeZone.prototype.getPlainDateTimeFor.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/TimeZone/TimeZone.prototype.getPlainDateTimeFor.js
@@ -35,7 +35,7 @@ describe("errors", () => {
         const instant = new Temporal.Instant(1n);
         expect(() => {
             timeZone.getPlainDateTimeFor(instant);
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 
     test("this value must be a Temporal.TimeZone object", () => {
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.getISOFields.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.getISOFields.js
index d1dd1fca4d..23b74df0d9 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.getISOFields.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.getISOFields.js
@@ -51,6 +51,6 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             zonedDateTime.getISOFields();
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offset.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offset.js
index 0e29735ec3..9778fb70a0 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offset.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offset.js
@@ -23,6 +23,6 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             zonedDateTime.offset;
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offsetNanoseconds.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offsetNanoseconds.js
index 3d72efe734..814db8b892 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offsetNanoseconds.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.offsetNanoseconds.js
@@ -23,6 +23,6 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             zonedDateTime.offsetNanoseconds;
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toJSON.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toJSON.js
index 4d74eda9e6..37924955f9 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toJSON.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toJSON.js
@@ -22,6 +22,6 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             zonedDateTime.toJSON();
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toLocaleString.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toLocaleString.js
index ba6c42fb2c..7e43fedb30 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toLocaleString.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toLocaleString.js
@@ -22,6 +22,6 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             zonedDateTime.toLocaleString();
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 });
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toString.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toString.js
index 21ea09b441..90bc7eae48 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toString.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.toString.js
@@ -156,7 +156,7 @@ describe("errors", () => {
         const zonedDateTime = new Temporal.ZonedDateTime(0n, {});
         expect(() => {
             zonedDateTime.toString();
-        }).toThrowWithMessage(TypeError, "null is not a function");
+        }).toThrowWithMessage(TypeError, "getOffsetNanosecondsFor is undefined");
     });
 
     test("calendarName option must be one of 'auto', 'always', 'never', 'critical'", () => {