Firefox Browser still shows timezone as GMT+01 for Africa/Casablanca
Hello, We are in Morocco, where Time zone has become GMT+00 or UTC after the 20th Sept 2026, the IANA has already published this change within 2026c update, but Firefox browser desktop still using GMT+1 for Africa/Casablanca time zone.
I've installed the latest Firefox desktop update until now : 156.0.1 (64-bit)
test : console.log("Detected IANA zone:", Intl.DateTimeFormat().resolvedOptions().timeZone); console.log("Date.toString():", new Date().toString()); console.log("getTimezoneOffset() (minutes):", new Date().getTimezoneOffset());
result: Detected IANA zone: Africa/Casablanca debugger eval code:1:9 Date.toString(): Sun Sep 27 2026 13:41:40 GMT+0100 (GMT+01:00) debugger eval code:2:9 getTimezoneOffset() (minutes): -60