Lightning 1.9.1 Release Candidate Available

We are happy to announce that a Release Candidate for Lightning version 1.9.1 is now available for testing here. For those using linux, please use the build in the linux/ folder rather than the platform-specific folders. Windows users can find their builds in the “unsigned” folder.

This version fixes an issue that prevents some events from being modified and some reminders from being dismissed in CalDAV calendars with Offline Support enabled – those affected are encouraged to test this build. If you have seen an error message with “this.mItemInfoCache[] is undefined”, this is you! Be sure to reset your cache, by unchecking the “Offline Support” checkbox, restarting, then checking it again.

The full list of changes in this version can be found here.

It is really important that you test this pre-release, as it will become the next release for Thunderbird 17. There is no additional beta phase, this is it! If you are using Thunderbird 17, please give it a try and let us know if you encounter any errors.


  1. Can’t install, not compatible with TB 17.0 ESR and there are not newer updates for ESR.
    When I open install.rdf I see minimal requirement is 17.0.2esrpre

    • Thanks for the comment. I will fix this asap. In the meanwhile, please just change it to 17.0 and maxversion 17.*

      Update: I’ve fixed this server side, it should show up on the live servers in a minute.

  2. Hi,

    Any ideas when 1.9.1 final will be released ?

    Thanks !

  3. Hello, for some reason since last update TB 17.0.3 and lightning 1.9.1 I am unable to add new event in thr Calendar. Nothing happens upon the pressing of the “new event” button and it will turn grey (inactive) until the next restart. Tried to re-install addon and TB – still no success. The error messages are as follows:

    Timestamp: 25/02/2013 13:50:03
    Error: Can’t create calendar for c934ac06-bc48-44c9-94b2-57ba917656f9 (storage, moz-storage-calendar://): [Exception… “” when calling method: [calICalendar::id]” nsresult: “0x804a0007 ()” location: “JS frame :: resource://calendar/modules/calUtils.jsm -> file:///C:/Users/Mikhail/AppData/Roaming/Thunderbird/Profiles/iin6miez.default/extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/calendar-js/calCalendarManager.js :: cmgr_assureCache :: line 706″ data: no]
    Timestamp: 25/02/2013 13:50:03
    Error: TypeError: currentView(…) is undefined
    Source File: chrome://calendar/content/calendar-multiday-view.xml
    Line: 2499
    Timestamp: 25/02/2013 13:50:03
    Error: ” when calling method: [calICalendar::id]
    Source File: resource://calendar/modules/calUtils.jsm -> file:///C:/Users/Mikhail/AppData/Roaming/Thunderbird/Profiles/iin6miez.default/extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/calendar-js/calCalendarManager.js
    Line: 538

    • matthew.mecca

      Is it possible that you used this profile with a development version of Thunderbird and Lightning higher than TB 17.0.3 and Lightning 1.9.1 before installing these versions? If so, it is not currently possible to downgrade the local calendar storage database, which can result in this error message when the earlier version attempts to load the calendar. As a workaround you could try using the same development version again (which should be able to access the database), then export the calendar to an .ics file, then create a new profile using TB 17.0.3 and Ltn 1.9.1 and import the .ics file.

    • Mikhail Keniya

      Thanks. That was my case, and everything is sorted now)

  4. Hey Phillip, could you pls explain how can I drag particular email and drop into some day so lightning could change it into an event or task?

    • matthew.mecca

      I don’t think this is possible with drag and drop at the moment, but you should be able to right-click on the email and use Convert To -> Event or Task

  5. Hi,

    I have the same question, when the final release will be release ?


  6. Tbird 17.0, Lightning 1.9

    I use a dark theme due to vision impairment from cataracts. The theme changes the font of the today panel in Lightning, but not the background, so I can’t read any of the text of upcoming events in the today panel. If you could give me a workaround for this I would certainly be very grateful.

    • matthew.mecca

      It the Thunderbird Preferences dialog, Calendar, General tab, there is a setting for “Optimize colors for accessibility”.

      • Thank you. That helped in previous versions, but not now. The dark theme I use employs gold font on a black BG. I now have gold font on the gray background in the even list of the today pan, which is unreadable to me.

        • matthew.mecca

          All-day events will show in the today pane with the background color of their associated calendar rather than the system color. You can change the calendar color in the Edit Calendar dialog by double-clicking on the calendar’s name in the calendar list on the left. If you have multiple calendars than you will have to set the background color of each one separately.

      • Thank you for the trouble of responding. I see I am unable to articulate my issue. I understand what you are telling me, but it doesn’t actually relate to my problem. There is no need of further reply.

  7. Madgey Stardust

    It was working, but now it doesn’t.

    I’m using

    – Ubuntu 12.04 LTS
    – Thunderbird 17.03
    – Lightning 1.9.1
    – Provider for Goolge Calendar 0.18

    Not sure when exactly this stopped working, but was about 2 maybe 3 weeks ago.

    Prior to that I had been using Lightning 1.9.

    Just extremely frustrating as it had been working, and now no matter how many times I remove and re-add the addons the Provider addon still will not work!

    Any ideas?

    • Madgey Stardust

      Managed to resolve this myself by ditching the Provider add-on and just using Lightning.

  8. Hello Philipp,

    Please bear with a new user.
    I’m on Postbox trying to get Lightening working with Mac Calendars (OS 10.8.2) I assumed this was functional from the Mozilla Sunbird/Lightning info quoted below:
    “iCal and Calendar use the same file format, so events from one should show up without problem in the other. You can also subscribe to the list of events on Apple’s website if you like.
    Please note that iCal is currently not capable of cooperatively editing a calendar file on a webDAV or ftp server. iCal will overwrite any changes made from a different application (like Sunbird or Lightning) on such a file.”


    Thanks for your time

  9. hi i just installed a fresh copy of lightning and am wondering if i can do the following:
    lightings vertical bar is cool , can i add MONTHS in the vertical bar? like display the current month on the right (without clicking the small indicator) ALWAYS show the full month on the right (current month and if possible next month too)

  10. A group of us in my department at work are using Thunderbird and Lighning and have been successfully for many years. However recently we have all found the when a reocurring meeting with a reminder appears we can not dissmiss the event it continuely reminds us until I delete the event.

    I know this happened before as I can read on the different forums but it is back. I have tried the following:

    1 updated to the latest Lightning 1.9.1
    2 made sure the calendar is not read only
    3 cleared the cache on lightning and thunderbird

    Still the same problem. we are attaching to a CALDev calendar “Convergence” and have two reoccuring events a week.

    Is there something we can do to solve this issue?

    • Are you able to make any other changes to the event that triggers the reminder? Lightning currently saves the reminder state with the event, which can cause problems if the event is read-only for any reason. If you are able to otherwise change the event, please file a bug at under the Calendar product.

  11. I have thunderbird 17.0.4 and started having issues with lightning, click on month advance arrow and lightning and thunderbird stop responding. I have reinstalled lightning, but still have same issue. I have disabled all add ons and still have same issue. What is happening? I have clicked on support link and was taken to blog section. Have searched mozilla site for help but could not find anything helpful. This problem has only occured since last two updates of thunderbird.

  12. Thanks for the non reply and removal of my question on this SUPPORT blog, which took me ages to locate.
    A response to my original question would be appreciated, since thunderbird and lighnting stop working when a button is clicked in lightning.

  13. Also, I have removed the review question, after your original response.

  14. It seems there are several possibility to update:
    _Tools | Options | Advanced Tab | Update (under-tab), Automatically search updates for: Th, Add-ons (checkbox)
    _Tools | Add-ons, Extensions sub-menu, Right-click on Ltn extension, then Find update.
    _Tools | Add-ons, Extensions sub-menu, Double-click on Ltn extension: Automatic Update: Default, Enable, Disable(Radio Button)

    How is it rules for Ltn specific purpose?

    • Now that Lightning 1.9.1 has been officially released, it should be automatically updated to the latest version if the settings you described are on. The right-click -> Find update will manually search for updates if the automatic update doesn’t work for some reason or if you have turned that off.

  15. I am using CalDav with google and have offline cache turned on, very large history of events, takes about 30 minutes to reload (offline off then back on) the cache during which Thunderbird is mostly “not responding”. I have the problem with being unable to Dismiss events and cannot delete those events that have trouble dismissing. If I delete the troubled event in google, Lightning still shows the event. Not all events have trouble, seems somewhat random.
    I am not getting the error…so, would this update not apply to me?
    If I update to the 1.9.1, will automatic updates work in the future?
    Is 1.9.1 expected to go full release soon?

    • Ok, got the released 1.9.1 and did the turn off offline cache, close thunderbird, restart and turn on offline. I still have an even that will not Dismiss. The event was an outlook invitation that I accepted. Neither Snooze nor Dismiss do anything, no errors though. I even tried to dismiss the event before turning Cache back on, won’t work. I can close the reminder window, but next time it syncs, the reminder reappears. I have had other events since this event and they do Dismiss properly. When this happened with the previous version, I think the reminder went away after a week or two.
      I know it is hard to trouble shoot, but just throwing it out there.

      • Are you able to make any other changes to the event that’s firing the reminder?

        • No, can’t make changes to the event. This event was accepted from an outlook email invitation about a month ago and is recurring monthly. So, I cannot change the meeting itself because of it being an invitation, but I tried to change the reminder from 1 hour before to 30 minutes before. I clicked ok to the change. Went back in and it is still set at 1 hour.

          • Thought I should add…I am using CalDav access with gmail and I also sync an ipad to the gmail. I also use zindus to sync the address book. I have calendar information going back many years and have about 6.5GB of email, most of which is in local folders. When clearing the calendar cache and going back to offline cache, it takes about 30 minutes for Thunderbird to respond again. In the past I have gone into gmail to delete the event, but the event stayed in lightning.
            However, Tried something new…just got the reminder to go away…I turned off cache and exited thunderbird. Logged into gmail via web and deleted just that occurrence of the repeating event. Entered a new event in its place. Then re-opened thunderbird, now the new event popped a reminder which I was able to dismiss. Then turned offline cache back on, waited the half hour caching time…FIXED (or at least its a work around).

          • Had another event that would not dismiss. It was recurring event monthly, but I scheduled it (not from outlook). Prior to the 1.9.1 update, I did a snooze for two weeks. When it reminded me today, I could not dismiss. Just closing thunderbird and reopening allowed me to dismiss it.

    • Lightning 1.9.1 has been officially released now.

  16. Thank you! This release fixed the reminder issue [#769118] for me.

  17. Repeating Tasks Kill Performance?

    Yesterday I upgraded Thunderbird to 17.0.4 (from 3.1.9), and Lightning to 1.9 and then 1.9.1 (from 1.0b2-tb) on Windows 7.

    With Lightning disabled, Thunderbird startup takes 5-10 seconds. Thunderbird process virtual size is around 295 MB (according to SysInternals Process Explorer). Most operations take less than a second.

    With Lighting enabled, Thunderbird startup takes more than a minute, process virtual size is around 2.5 GB(!), and all Thunderbird operations are sluggish. For example, bringing a window to the front or selecting a tab takes half a minute, often more. Selecting a Reminder can take about a minute. Dismissing a reminder takes 5-10 seconds.

    I use several ICS calendar files, some of which have quite a few daily and weekly repeating tasks. The Tasks tab shows many repetitions of the same task (note years 1994-1995 in I cannot scroll down more than one page; it just hangs. My guess is that Lightning is instantiating every occurrence of every repeating task, and perhaps iterating through these instances for various operations.

    Last time I updated was two years ago. Did I miss a change in philosophy of repeating tasks?

    — Thanks

    • Before Lightning version 1.0b3, repeating tasks weren’t fully supported, so you couldn’t click the check box to mark them as complete or otherwise edit a single occurrence in the task list the way you could with non-repeating tasks. That has been fixed, along with the task view filters that would drop old tasks off the list whether they were completed or not.

      In your cases this presents the problem that Lightning sees all of the old occurrences as still incomplete, so it tries to show all of them in the task list. The easiest way to fix this would be to switch to the “All” filter on the task tab, that will show only one entry on the list for a repeating task instead of the occurrences. From there, you can edit each of the repeating task and set the dates forward (so for example if you have a weekly task on Monday, set the start date to next Monday). Once that’s done for all of them, you can switch back to another filter and it should be much more responsive. Going forward, you can mark each task occurrence as complete individually.

  18. This morning lightning stop working. I try to re-install, but I’m unable to install it, now. why?

  19. with Thunderbird 17.0.4 & Lightning 1.9.1, none of my events from my four ics files show up.

    Text from Error Console follows…
    Timestamp: 3/18/2013 11:28:27 AM
    Warning: WARN addons.xpi: Ignoring missing add-on in C:\Program Files\AVG\AVG2012\Thunderbird
    Source File: resource:///modules/XPIProvider.jsm
    Line: 6725

    [calTimezoneService] using C:\Users\Joseph H. Cardana\AppData\Roaming\Thunderbird\Profiles\flf7cfb8.default\extensions\{e2fda1a4-762b-4020-b5ad-a41df1933103}\timezones.sqlite

    [calTimezoneService] timezones version: 1.2011nTimestamp: 3/18/2013 11:28:43 AM
    Warning: Error in parsing value for ‘padding-bottom’. Declaration dropped.
    Source File: chrome://messenger/skin/messenger.css
    Line: 401

    Timestamp: 3/18/2013 11:28:45 AM
    Warning: Use of Mutation Events is deprecated. Use MutationObserver instead.
    Source File: chrome://calendar/content/widgets/calendar-widgets.xml
    Line: 306

    [calICSCalendar] Refreshing Joe’s Personal

    [calICSCalendar] Error occurred opening channel: [Exception… “Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIChannel.asyncOpen]” nsresult: “0x80004005 (NS_ERROR_FAILURE)” location: “JS frame :: file:///C:/Users/Joseph%20H.%20Cardana/AppData/Roaming/Thunderbird/Profiles/flf7cfb8.default/extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/components/calICSCalendar.js :: calICSCalendar_doRefresh :: line 194” data: no]

    [calICSCalendar] Refreshing Joe’s Professional

    [calICSCalendar] Error occurred opening channel: [Exception… “Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIChannel.asyncOpen]” nsresult: “0x80004005 (NS_ERROR_FAILURE)” location: “JS frame :: file:///C:/Users/Joseph%20H.%20Cardana/AppData/Roaming/Thunderbird/Profiles/flf7cfb8.default/extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/components/calICSCalendar.js :: calICSCalendar_doRefresh :: line 194” data: no]

    [calICSCalendar] Refreshing Tami’s Professional

    [calICSCalendar] Error occurred opening channel: [Exception… “Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIChannel.asyncOpen]” nsresult: “0x80004005 (NS_ERROR_FAILURE)” location: “JS frame :: file:///C:/Users/Joseph%20H.%20Cardana/AppData/Roaming/Thunderbird/Profiles/flf7cfb8.default/extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/components/calICSCalendar.js :: calICSCalendar_doRefresh :: line 194” data: no]

    [calICSCalendar] Refreshing Tami’s Personal

    [calICSCalendar] Error occurred opening channel: [Exception… “Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIChannel.asyncOpen]” nsresult: “0x80004005 (NS_ERROR_FAILURE)” location: “JS frame :: file:///C:/Users/Joseph%20H.%20Cardana/AppData/Roaming/Thunderbird/Profiles/flf7cfb8.default/extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/components/calICSCalendar.js :: calICSCalendar_doRefresh :: line 194” data: no]

    [calFilterProperties] Applying filter:
    start: 0
    end: 3
    status: 3
    due: 15
    category: null

    [calFilterProperties] Applying filter:
    start: 0
    end: 3
    status: 3
    due: 15
    category: null

    [calFilterProperties] Applying filter:
    start: 0
    end: 3
    status: 3
    due: 15
    category: null

    Timestamp: 3/18/2013 11:28:57 AM
    Warning: XUL box for box element contained an inline #text child, forcing all its children to be wrapped in a block.
    Source File: chrome://messenger/content/messenger.xul
    Line: 0

    Timestamp: 3/18/2013 11:28:57 AM
    Warning: XUL box for box element contained an inline #text child, forcing all its children to be wrapped in a block.
    Source File: chrome://messenger/content/messenger.xul
    Line: 0

    [calFilterProperties] Applying filter:
    start: 0
    end: 3
    status: 3
    due: 15
    category: null

  20. How to Add apple calendar

  21. Hi, since TB was updated to 17.0.4 and 17.0.5 I cannot snooze or close event alarms in my CALDAV Google calendars anymore nor can I create new events (Lightning 1.9.1). Going back to TB 17.0.3 solves the problem. I ran into the same problem a while ago, but don´t remember the version at the time – anyway it had then been solved with an update for Lightning.

  22. Using Lightning 1.9.1 with Thunderbird. How can I print a monthly view of the calendar rather just a list ?


  23. Felix Schweizer

    I love Thuderbird and I love Lightning, but the hangs with Lightning are getting worse with every release! I am using a google calendar as a shared tool and thus need provider for google calendar. I know this is a known problem, so I am just asking whether there is any solution in sight or whether those of us who have to use the google calendar just are SOL?

    As stated, the problem is getting worse, not better, with the hangs getting more frequent and longer with every new release of TB…

  24. Nice work.

    I believe it would be nice if the “Convert To => Event” had the option to automatically add the e-mail recipients as Event attendees.

  25. Georges Orwell

    I still have the issue with the reminders.
    Thunderbird 17.0.5 with Lightning 1.9.1


  26. Regarding the issue that reminders can’t be dismissed:
    It looks like the reminders aren’t synched unless something else about the event changes.

    I tested this in Thunderbird 17.0.5, using Lightning 1.9.1 and a Google calender added using the CalDAV url.

    Changing only the reminder in an existing event is disregarded by the synchronization entirely, no matter ion which side the change occurs. Only changing the name on the same side will make the reminder change sync.

  27. Just as user “Charlie” above, I can’t dismiss or snooze any reminders for a Google calendar accessed via CalDAV. I read at that Philipp says that this might be a Google Calendar Server bug caused by a recent change on Google’s side. Is there an issue logged at, like the old, that we can follow to find out when this issue is fixed?

  28. I can not dissmiss reminders since the last update of thunderbird ?
    This is very annoying.
    win7 64
    thunderbird 17.0.5
    ligthning 1.9.1

    Thanks for your help

  29. Konstantin Boyandin

    The ‘stuck reminder’ problem persists for me (Lightning 1.9.1) and is extremely annoying.

    The only solution I found was to disable entirely the reminders for past/missed events, that’s the only way to make ‘Dismiss’ butoons work for me.

    OS: Ubuntu 12.04 64-bit, Thundebird: 17.0.5
    I would appreciate any working solution without disabling the above option and without restarting Thunderbird now and then.


  30. THUNDERBIRD version = 17.0.6
    LIGHTNING = 1.9.1

    Hello, I’d like to use Lightning in order to remind my colleagues (and myself!) about important events.
    Unfortunately, when I create a NEW EVENT, I can “INVITE” whoever I like (selecting e-mail addresses from my TB phone-book) but the tick box “notify attendees” is not active (gray).
    Result: no invitations/e-mails are being sent.
    Am I doing anything wrong or missing any settings?
    Thank you in advance for your help with this issue !!

  31. I received the following calendar invite (edited for privacy) recently, I get “This message contains an event that this version of Lightning cannot process.” Using Tb 21, Lightning 2.3b2.

    Hopefully the code tags work. I got the code using Notepad++ and only edited for privacy the message, location, senders email address, and name. The ‘m’ from ‘.com’ in the email address was on a separate line.

    PRODID:Microsoft Exchange Server 2010
    SUMMARY;LANGUAGE=en-US:New Time Proposed: Event Invitation: New Event

    • same issue : this msg contains an event… lightning cannot process

      email appears empty, view source displays as above ( @ tbbetauser )

      However, hit reply, (to the mail) and you will see ( at least I do ), the event details window with the necessary info: event subject date, time etc.

      Not a fix but at least you see the info

  32. I cannot create custom repeats with this most current version of Lightning. No box pops up to create it and the program freezes every time. I have to alt ctrl delete to stop it and thunderbird closes too. There are multiple errors on the error console.
    Ex. Ruleset ignored due to bad selector, Use of mutation events is deprecated, error reading data. Some codes are: DAV_NOT_DAV and READ_FAILED. Any ideas? Thanks.

  33. Hi,

    The recent update (of 15 May 13)–leaving me with thunderbird 17.-0.6 and lightning 1.9.1– has debilitated my lightning. When I try to add a new event, I cannot add any events: a new event pop-up window comes into existence, but it’s always underneath the main thunderbird window. Lots of wild messages in the error console, but they offer no consolation– I don’t know what to do with them. I’ve tried downloading 1.9, If you’ve some ideas what to do, I’d be grateful.

    Thanks– jvm

  34. I have issues with calendars using CALDAV from yahoo. The issues comes when i edit an event of one calendar from yahoo to another calendar. It should be create the copy for the new calendar and delete the old one, and it seems to do it visually. But when i look again 5 minutes laters, theres no event.. I try it looking in yahoo calendar website and it dissapears at the moment of changing calendar.

  35. Excuse me.
    How to share calendar (all user)
    And user can update calendar
    thank you

    • Philipp Kewisch

      You will need a remote calendar server, like Google or Yahoo or a self-hosted caldav server.

  36. I’ve been using google calendar without Provider for some years now, just by configuring the location of the remote calendar in

    which requires username and password to access the remote calendar.

    I don’t like programs to store my passwords, so I type username and password every time I start thunderbird. Recently, I have started using several google calendars, so I have to type the usernames and passwords for each of them (and all of them are different). The problem here is that the login dialogs appear in a different order every time I start thunderbird, and there is no clue on which account I’m logging in, so I have to randomly type all the user information and restart thunderbird if any of them are wrong.

    There’s an obvious solution which is to remember passwords, but I guess it would be better to identify accounts in the login dialog (just like thunderbird does with email accounts).

    Any chance this could be done? BTW, I’m currently using lightning 1.9.1 and TB 17.0.7

    • Philipp Kewisch

      You could try setting to true in the advanced config editor. You might need this anyway if you are using multiple calendars with different passwords. The calendar name will be added to the realm in that case.

      Note that soon Google will require OAuth2, where things might work completely different. Try the latest beta builds to see how it works out for you.

  37. Using:
    Thunderbird 17.0.8
    Lightening 1.9.1

    Functionality request:
    Please add option to set the days for reminders (past reminders).
    Currently I can make out that past 30 days reminders are available when the “Reminders” window pops-up. I would be thankful if the days are settable beyond this 30days limit.

  38. I access calendars over HTTPS on a webdav server. I have offline support disabled. Since upgrading to 1.9.1 I have had the following problems:

    1. The calendars are EXTREMELY slow to load. I am talking about minutes just to display them, and every time thunderbird thinks it needs a refresh. It’s painful really. Was working fine before, and on manually checking the server I can confirm that the response is just as speedy as it has ever been.

    2. The dismiss and snooze functionalities is completely broken. The first dismiss will typically disappear instantaneously. However, if I click a second dismiss too soon (I mean, without waiting at least 1 minute then it appears to just stay there even though I have clicked dismiss. Sometimes it will eventually be dismissed after ~several minutes if I wait. If I click dismiss on another one while waiting, then it will cause a calendar modification error. Sometimes the dismiss just never disappears. While waiting for the dismissal, the display of event can go blank and wont refresh. I am forced to restart TB and then the calendard is in read-only mode. I take them out of read-only mode. Force a reload. Wait ages for the view to refresh… and finally all the reminders pop up again so I am back to square one!!! What a pain. If I hit snooze all, this is gauaranteed to fail and force me to restart to get the calendars working again.

    Again, previously, this was all working just fine. I would hit dismiss and it would be gone within a few seconds. It seemed to me as if TB must have been having a huge back and forth chat with the server when it should be a simple as “issue command”, “get response”. However, I have had a look at the server logs in realtime and that’s not the case. TB is simply waiting random amounts of time (but at least 30s, and often significantly more and sometimes effectively forever!) before even making any requests to the server! Then it gets its responses responses (GET, PUT, PROPFIND) back in quick succession. If there is some other calendar action before it has sent its requests to the server (which, if it is taking 5 minutes is bound to happen), then it seems to freeze up completely.

    I have tried stopping TB, renaming my calendar-data/cache.sqlite file, and restarting, but this didn’t help at all.

    Re “This version fixes an issue that prevents some events from being modified and some reminders from being dismissed in CalDAV calendars with Offline Support enabled – those affected are encouraged to test this build.” Seems like this change may have had large unexpected consequences which weren’t properly tested. I hope this can be addressed with urgency.

  39. I’m using Lightning with Postbox and Google provider extension. I’d like to change my “new event” time setting to 12-hour (instead of 24-hour). Any ideas? I’ve been researching a fix for a while and haven’t come across anything. Thanks!

    • Philipp Kewisch

      The 12/24 hour setting is usually an Operating System setting, I don’t think we do anything special here. Please check your OS settings, and if its already 12 hour, please reply with which OS you are using.

  40. I was using Thunderbird and updated automatically to v24 and found out that my ldap wasnt working so i installed 17.0.9 ESR and installed lightning 1.91. but i cant create a new calendar or tasks. The buttons dont do anything.-

  41. Thunderbird: 17.06
    Lightning: 1.9.1

    I can’t add new event and task, when i click the “New Event” in today panel, noting response. urgent!!! Do you have solutions for this?

    Thank you so much!

    • Philipp Kewisch

      Check your error console for messages. When 2.6.1 is out you might consider upgrading both Thunderbird and Lightning.

      • Thank you Philipp!!

        Thunderbird 24 with the lightning 2.6.1 work normal, But I like to use Thunderbird 1.7 since some plugins not work well in thunderbird 24, for example: Color folders is my favorites plugins, but it’s not work in TB version 24.