The Message Filters are best used for managing emails eg: Move to a folder

You can use Message Filters for spam but you end up spending most of your life creating tons of filters. Maybe you can use less filters by one which test for several similar conditions - example 'Match any of the following' option betreff enthalt Exklusiver deal Adding a new criteria - clickon + to get a new line then enter next data betreff enthalt Confirmation Adding a new criteria - clickon + to get a new line then enter next data betreff enthalt Notification

So you can have several in just one filter. If email matches ANY of the following - which then lists various options then Move to Junk

Personally, I have found it's much easier to use the Junk Controls in each account. Once you have trained Thunderbird as to what is junk and also what is not junk then you do not need to create so many filters just for spam. https://support.mozilla.org/en-US/kb/thunderbird-and-junk-spam-messages

Thunderbird does have a list of all filters you create. It is stored in a file called 'filterlog' and it's located in the profile folder in the account name folder. eg for an imap account: C://Users/User name/Appdata/Roaming/Thunderbird/Profiles/profile name/ImapMail/account name folder

You can open that file using notepad, but if want a copy - exit Thunderbird first then copy the file to desktop where you open it using a text editor.

Did not find a file named 'filterlog', but I did find a file named 'msgFilterRules.dat' in the location specified (C://Users/User name/Appdata/Roaming/Thunderbird/Profiles/profile name/ImapMail/account name folder). In my case, the folder name is not the name of the account but the name of the inbound server (e.g., 'imap.ionos.com').

I gave up using Thunderbird junk filtering. Instead, I have a filter that sends anything not in my address book to spam and another that sends anything in my address book to the inbox. I do have to check spam periodically and add someone or some organization to the address book. To keep my address book from being cluttered I set up a separate address book called "allowed organizations." Sometimes the same organization uses different addresses from the same domain. To cover those cases I have an exceptions filter that moves any message from the set of domains listed (specified by using, e.g., "ends with 'usps.com') to the inbox. (The exceptions are repeated in the filter that sends messages not in my address books to spam.)

The main problem with this setup is that I use two computers and have had to track down where address books and filters are stored to keep them in sync. The personal address book is stored in a file called “abook.sqlite.” Other address books need to be exported and imported. The message filters are stored as described above.

IMAP works very well for keeping messages synchronized among various devices. In addition to my two computers, I have a phone and tablet. I use all four devices for email, but let the computers manage the junk filtering. It would be desirable if mail clients like Thunderbird could devise a common means of sharing address books and filters through the cloud, so that an update on one machine is immediately reflected on another. Thunderbird could develop such a means on its own, yet it would be better if that paved the way for providing sharing addresses and filters among various clients. One way might be for Thunderbird to allow the use of other address books (like Google’s) in place of (or in addition to) its own. My Samsung phone, for example, allows you to select where an address is stored. Google Contacts is one of the choices. It’s confusing on Samsumg, because it’s not always clear what choice you’ve made, but the idea is a good one: allow users to store addresses in a place that is readily shareable.

My error...The file : 'filterlog.html' contains a log of what filters moved what emails to where. The 'msgFilterRules.dat' contains all the rules set for that account and can be copied and pasted into the 'mail account folder' in a another profile. When copy pasting files Thunderbird must not be running.

Other things that Thunderbird offers: In Address Books:

1. Add new address book
2. Add Carddav address book
3. Add LDAP address book

eg: For a CardDAV Address Book:

• Open an Address Book tab.
• Click on the 'New Address Book' icon (located left of '+New contact')
• from drop-down select 'Add CardDAV Address Book'
• Enter your User Name and URL for your server.
• Press Continue, and follow the instructions.

Also for LDAP servers:

• Settings > Composition
• scroll tp 'Addressing'
• check "Directory Server"
• click 'Edit Directories'.
• Click 'Add' and fill in the required information:

There is also this addon: if you like it please offer donation for continuation of maintenance. https://addons.thunderbird.net/en-GB/thunderbird/addon/cardbook/

If you have a gmail account and use a Google calendar then you can synch between them. Thunderbird calendar does allow connecting to other calendars. https://support.mozilla.org/en-US/kb/creating-new-calendars