User Agent: Mozilla/5.0 (Windows NT 5.1; rv:40.0) Gecko/20100101 Firefox/40.0 Build ID: 20150826023504 Steps to reproduce: Hibernate my PC overnight Actual results: Today pane still shows date that PC was hibernated Expected results: Today pane should update to current day This problem only appeared with a recent update (v38, I think)

After hibernae, does the condition clear if you do File | Offline | Work Offline to set offline mode, and then do Work Offline again to set it back to online?

Bug 1196662 occurs in Tb 38.2.0. If issue in Tb 38.2.0, and if issue after hibernation, and if problem is critical for you, try Tb 38.1.0 until the bug will be fixed, please. .

As this is a bug report for calendar, it's eventually the same as bug 1199994.

According to Bug 1196662 Comment 81 it seems this is just one effect from a core bug that affects sleep mode. Bug 1196662 Comment 81 suggests a workaround that you can test.

It looks like I am actually seeing Bug 1196662 / Bug 1197152 Emails were delayed too - I usually rely on the taskbar notification and otherwise ignore Thunderbird. Apparently the whole thunderbird user interface is not being redrawn. The menu works, clicking on tabs or folders updates the window title but nothing else visible happens.