Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More
This thread was archived. اگر به کمک نیاز دارید لطفاً یک سؤال بپرسید.
Solved Archived

Mozilla Thunderbird not matching time format of the OS

Thunderbird Customization
Eugene Denisov replied
Eugene Denisov
Eugene Denisov

I'm running Thunderbird 140.0.1 (64-bit) on Windows 10. The problem is Thunderbird is showing wrong format. My system's sets are: Short date: dd.MM.yyyy Long date: dd MMMM yyyy 'г.' Short time: HH:mm Long time: HH:mm:ss

Thunderbird's language is set to English (US). And it shows times as: 1:00 AM, 2:00 PM etc. Tried to change it to en_GB, did nothing at all. Changing it to ru_RU affects the time format, but interface goes Russian which is unwanted.

Please help to fix it. It's crucial for me to have 24h format as otherwise I cannot use mail/calendar because it's misleading.

I'm running Thunderbird 140.0.1 (64-bit) on Windows 10. The problem is Thunderbird is showing wrong format. My system's sets are: Short date: dd.MM.yyyy Long date: dd MMMM yyyy 'г.' Short time: HH:mm Long time: HH:mm:ss Thunderbird's language is set to English (US). And it shows times as: 1:00 AM, 2:00 PM etc. Tried to change it to en_GB, did nothing at all. Changing it to ru_RU affects the time format, but interface goes Russian which is unwanted. Please help to fix it. It's crucial for me to have 24h format as otherwise I cannot use mail/calendar because it's misleading.
Attached screenshots

All Replies (1)

Eugene Denisov
Eugene Denisov Question owner

Chosen Solution

No worries, I've found the answer, it's done through adding intl.date_time.pattern_override.date_short and intl.date_time.pattern_override.time_short string preferences, which shall override any other formats.