GNU Icecat always on UTC

I am on Debian bullseye, and I use GNU Icecat as my main browser. It is my favorite browser, but it irks me that its time zone is always UTC, though I am in a different one. I see this because some websites detect my browser's time zone and compare it with the account time zone. ---- I tried running it while passing an environment variable: TZ='US/Pacific' icecat I ran the following in the JS Console: new Date().getTimezoneOffset(); The offset returned by IceCat is always 0. Firefox returns it as per the time zone, but I am not sure how - it doesn't seem to obey the TZ variable either. ---- Is this a bug with Icecat itself? A privacy-preservation measure? A configuration error? The Debian package? *I don't think it's the Debian package, because it was not installed via APT.* In any case, I would like to have the proper time zone returned. How do I fix it? In case it's relevant, my build version is 60.3.0esr (64-bit).