User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 Build ID: 20151029151421 Steps to reproduce: In my country Monday is considered the first day of the week and I have set this in the Lightning settings. This works fine and the week view displays the week from Monday to Sunday. But each time the Lightning Add-On is updated, the first day of the week is reset to Sunday. Actual results: After the update the week view displays the week from Sunday to Saturday and the Thunderbird Lightning settings UI reports Sunday as the first day of the week. Expected results: The preference of that setting should also be transferred when the Add-On is updated.
What localization are you using? Is this also fitting to your location? On what OS are you? If on Linux, do you install from package manager or from Mozilla website / in product update?
I use the German Version of Thunderbird and I'm located in Germany. Thunderbird 38.4.0 with Lightning 22.214.171.124 on Win7/x64. Normal update with the internal Thunderbird Add-On-Update mechanism.
Thanks. I can confrim this. Other than the bundled builds, the AMO builds don't seem to ship localized default prefs with an lightning-l10n.js. So, this may lead to reset the prefs. Phillip, any thoughts on this?
See Bug 395504. A workaround might be to create a user.js (http://kb.mozillazine.org/user.js_file) with the first day setting in it.
I think we should fix bug 395504 instead. I could imagine doing so by using nsIPrefService::readUserPrefs on lightning-l10n.js of the currently loaded locale, given that doesn't overwrite user.js and custom set preferences.
I don't get it: why is this pref overriden every time Thunderbird updates Lightning while other prefs are not? It's painful to have to fix the first day of the week after each update.