Betterbird: Support

Bugs, bugs, bugs, ...

Let's start with the bad news. At time of writing, 21st June 2023, Bugzilla shows 15.498 open "tickets" in Thunderbird (components Thunderbird: 8744, Mailnews Core: 4340, Calendar: 2183, Chat Core: 231, up from 14.312 in August 2021, Bugzilla can't retrieve more than 10.000 bugs, you need to query separately), not counting the bugs in the Mozilla platform code that affect Thunderbird (like in the Editor, Spellchecker, Serialiser, etc.). Not all "tickets" are bugs, of course, but a fair portion is. Chances are that you are experiencing one of those.

We are here to help with bugs
(not account setup, profile management or configuration)

So what do to? In general, we're here to help, but as you will understand, our small team cannot fix all 10.000+ bugs given that some of them are two decades old and the Thunderbird team which has many more resources than we do haven't addressed those bugs.

As a first step, we suggest installing the current/matching ESR version of Thunderbird in parallel and see whether the issue exists there. If so, it's a good idea to check whether a bug has been reported already at Bugzilla. If the issue exists in Thunderbird, regardless of whether it has been reported at or not, you can contact us and we can check how hard it would be to fix the issue. We may also advise you to file a bug in Bugzilla, so we can offer our fix to upstream Thunderbird, or we may choose to file the issue ourselves. Generally the idea of Betterbird is that our team tries to provide users with a better experience and that involves fixing long-standing and annoying bugs that somehow the Thunderbird team is not addressing.

If the issue only exists in Betterbird, please contact us immediately and we will endeavour to get a fix to you as soon as possible. Or you can file an issue at our Github repository.

In any case, common sense bug reporting rules apply, so something that's not reproducible won't be fixed and the user needs to cooperate during the debugging phase by following our suggestions and providing feedback or debugging information.


Understandably we cannot give user support with account setup, profile management, configuration customisation (incl. developing userChrome.css) or troubleshooting individual problems. Since Betterbird and Thunderbird are very similar, users have access to a plethora of online resources, forums and newsgroups to discuss their issues. For example, there is a very active German forum where you can join the discussion.

We don't have the capacity of personally guiding or instructing all our users. Should you contact us with an individual issue, if we chose to troubleshoot the issue, this support will not be free of charge and a minimum donation to the project will be required.

How to switch between Thunderbird and Betterbird?

Betterbird is designed to be 100% compatible with Thunderbird of the same version. For example at time of writing you can switch between Betterbird 102.2.0-bb14 and Thunderbird 102.2.0 without problem. Betterbird uses Thunderbird's profile directory and contained profiles for easy switching:

If Betterbird doesn't already detect your Thunderbird profile, start Betterbird with the -p option which will launch the profile manager. You can select your regular profile there. Important: If you're switching between Thunderbird and Betterbird, also use the -purgecaches option to avoid incompatible remnants of the other program in the startup cache. Another option is to view all profiles via Help > More Troubleshooting Information. Click on the about:profiles link which will take you to a tab where you can select a different default profile.

Warning: We have had many support cases where things don't work in mysterious ways after using the import function to import a Thunderbird profile. This functionality comes directly from our Thunderbird base and appears to be deficient. So please use with care. We're unable to support users who have used the import function.

It's better to manually copy a Thunderbird profile in the OS if you require a copy in the first place instead of running Betterbird on an existing Thunderbird profile. Brief instructions: Run betterbird -p to create a new profile taking note of profile name and storage location. After closing Betterbird, replace the content of the newly created profile folder with the content of an existing profile folder.

Things to keep in mind:

What's the story with the portable version?

Neither Thunderbird nor Betterbird are designed for portable use. The profile contains files which record native absolute path names (folderCache.json, prefs.js, extensions.json, addonStartup.json.lz4) and as soon as you move the profile, things break. The Thunderbird team do not offer a portable version and they are not connected to all the portable apps that exist. PortableApps.com is the the most well-known and sophisticated, they even have a trademark deal with Mozilla. They mitigate the native absolute path issues and their portable cleans up these folders C:\Users\<user>\AppData\Local\Thunderbird and C:\Users\<user>\AppData\Roaming\Thunderbird.

By popular demand, Betterbird ships officially as a portable version, but it has the same issues mentioned above. We've written our own simple launcher program, BetterbirdLauncher.exe whose source is published. As of January 2023 in version 102.7.1-bb29 the launcher program can be registered as default e-mail application using, for example, PortableRegistrator. Once registered, the launcher program must be selected as default e-mail app in Windows, see screenshot here. When registered, mailto: links will open in the portable Betterbird.

Update September 2023: From Betterbird 115.3.0-bb13 we are shipping a new launcher program which fully supports moving the portable folder.

A word about moving the portable profile, the initial purpose of portable applications: When moving the profile, it is possible that add-ons don't work any more. In that case, delete the add-on startup cache in profile\addonStartup.json.lz4 and set preference extensions.startupScanScopes to 5 (or 7 when using light weight themes) in the Config Editor.

What's the story with complex search terms in filters, folder search and virtual/search folders?

By popular demand, Betterbird implemented complex search terms starting in Betterbird 91.9.0-bb31. To implement that, we had to change the syntax of the content of the msgFilterRules.dat file that stores the rules a little bit while staying 100% compatible with Thunderbird as long as no complex search terms are used. In other words: If you only use simple search, you can switch between Thunderbird and Betterbird with no problem. If you use complex search terms, opening the Message Filter panel (Tools > Message Filters) will damage the complex filters set up in Betterbird. Just starting Thunderbird won't do any damage. If you set up search folders using complex search terms, they won't work in Thunderbird.

Is Betterbird a virus?

Sometimes virus scanners raise an alert for the Betterbird installer or the installed executable. If you've downloaded the installer from our website, these are false alarms. You can submit alleged malicious code to a recognised online virus scanner like VirusTotal or Jotti. We are self-signing all executables, you can download our certificate which you need to install into "Trusted Root Certification Authorities" (check with certmgr.msc). The result looks like this. For our own use, we've excluded the Betterbird program directory and process from further scans.

Betterbird doesn't contain any more malicious code than the Thunderbird or Mozilla codebase, but we admit that we haven't inspected the millions of lines of upstream code. The binaries we distribute are built from open source code and you can build the package yourself using the instruction on the Github repository.

One word of caution: E-Mail in general is dangerous. Like all written communication, it doesn't convey any facial expression, tone of voice and irony is frequently misunderstood. So use e-mail wisely and don't pick a fight! Also, e-mail is dangerous when sending the wrong stuff to the wrong people. Please check twice to whom you're sending the message before clicking "Send". We speak from experience :-( - If you're transmitting confidential information, you should consider setting up OpenPGP or using p≡p

Lastly and humorously: Some consider the Windows operating system to be a boot sector virus. We hope Betterbird will spread like a virus, and we need you to make the project a success.