From 2cd9657ae18af0969fef4c56d310a2a5bea7fec1 Mon Sep 17 00:00:00 2001
From: seojcarlos <jcarlos@convertiam.com>
Date: Tue, 7 Apr 2026 21:24:11 +0200
Subject: [PATCH] fix: prevent NaN timestamps from breaking event charts in
 Firefox

When date-fns-tz zonedTimeToUtc returns Invalid Date in Firefox,
the unary + operator produces NaN, which gets sent as "NaN" in
query parameters. Routes using z.coerce.number().int() validation
(events/series, event-data/properties) reject NaN as non-integer,
returning 400 errors and showing "Something went wrong".

This fix:
- Falls back to raw date timestamps when timezone conversion
  produces NaN in useDateParameters
- Filters out NaN values in getQueryString to prevent invalid
  parameters from reaching the server

Fixes #4121
---
 src/components/hooks/useDateParameters.ts | 7 +++++--
 src/lib/url.ts                            | 2 +-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/components/hooks/useDateParameters.ts b/src/components/hooks/useDateParameters.ts
index d84b4236a..6600ce8bc 100644
--- a/src/components/hooks/useDateParameters.ts
+++ b/src/components/hooks/useDateParameters.ts
@@ -7,9 +7,12 @@ export function useDateParameters() {
   } = useDateRange();
   const { timezone, localToUtc, canonicalizeTimezone } = useTimezone();
 
+  const startAtValue = +localToUtc(startDate);
+  const endAtValue = +localToUtc(endDate);
+
   return {
-    startAt: +localToUtc(startDate),
-    endAt: +localToUtc(endDate),
+    startAt: Number.isFinite(startAtValue) ? startAtValue : +startDate,
+    endAt: Number.isFinite(endAtValue) ? endAtValue : +endDate,
     startDate: localToUtc(startDate).toISOString(),
     endDate: localToUtc(endDate).toISOString(),
     unit,
diff --git a/src/lib/url.ts b/src/lib/url.ts
index f6772feec..a4cc7cb30 100644
--- a/src/lib/url.ts
+++ b/src/lib/url.ts
@@ -2,7 +2,7 @@ export function getQueryString(params: object = {}): string {
   const searchParams = new URLSearchParams();
 
   Object.entries(params).forEach(([key, value]) => {
-    if (value !== undefined) {
+    if (value !== undefined && value !== null && !Number.isNaN(value)) {
       searchParams.append(key, value);
     }
   });