fix: prevent blank screen crash when clearing timezone search field

client/src/Features/UI/uiSlice.ts

@@ -89,7 +89,9 @@ const uiSlice = createSlice({
 		},
 
 		setTimezone: (state, action: PayloadAction<{ timezone: string }>) => {
-			state.timezone = action.payload.timezone;
+			if (action.payload.timezone) {
+				state.timezone = action.payload.timezone;
+			}
 		},
 		setLanguage: (state, action: PayloadAction<string>) => {
 			state.language = action.payload;

client/src/Pages/Settings/index.tsx

@@ -127,8 +127,8 @@ export const SettingsPage = () => {
 		timezoneOptions.find((tz) => tz.id === selectedTimezoneId) ?? null;
 
 	const handleTimezoneChange = (newValue: Timezone | null) => {
-		const newId = newValue?.id ?? "";
-		dispatch(setTimezone({ timezone: newId }));
+		if (!newValue?.id) return; 
+		dispatch(setTimezone({ timezone: newValue.id }));
 	};
 
 	const handleModeChange = (e: SelectChangeEvent<ThemeMode>) => {

client/src/Utils/TimeUtils.ts

@@ -19,8 +19,11 @@ export const formatDateWithTz = (timestamp: string, format: string, timezone: st
 	if (!timestamp) {
 		return "Unknown time";
 	}
-	const formattedDate = dayjs(timestamp).tz(timezone).format(format);
-	return formattedDate;
+	try {
+		return dayjs(timestamp).tz(timezone).format(format);
+	} catch {
+		return dayjs(timestamp).utc().format(format);
+	}
 };
 
 export const tickDateFormatLookup = (range: string) => {