• In Thunderbird's "Tools" menu, select "Sieve Message Filters".

• In the panel that's displayed, under your Nevis mail account click "Connect".

• Under "Tools" select "Sieve Message Filters"

A practical example

Using ManageSieve on the Nevis mail server

On the Nevis mail server, the Sieve protocol is handled by Pigeonhole ManageSieve Server of the Dovecot IMAP server.

Using webmail

The simplest way to access and edit your Sieve configuration is:

• Login via Nevis webmail.

• Click on the "Settings" icon near the upper right-hand corner of the page.

• Leave the "Filter Sets" panel alone. Unless you want to switch between different sets of filters, the default managesieve set will do.

• Click on "Filters" in the left-most panel, "Settings".

• Click on the big plus ("+") sign on the bottom of the middle "Filters" panel to create your first filter.

The rest is pretty much self-explanatory. Don't forget to hit the "Save" button after you've created your first filter. Note that you can create as many filters as you want, each with a different name, and selectively enable/disable them.

A practical example.

Reminder from the Mail Filters page: Every time a LArSoft developer makes a change to the LArSoft git repository, I get an email message from larsoftcommit@fnal.gov or uboonecommit@fnal.gov. Frequently I get dozens of such emails every day. I don't want to automatically delete them, since there may be something that impacts my work, but I don't want them cluttering my INBOX either.

So I use a mail filter to test if the "From" address of each email I receive includes larsoftcommit@fnal.gov or uboonecommit@fnal.gov. If it does, the mail is immediately sent to my LArSoft commit folder instead of my INBOX. Periodically I review the contents of that folder to see if any code changes are relevant to me.

When I implemented this filter using Sieve in webmail, this is what I see:

Using Thunderbird

If you prefer, you may be able to edit Sieve filters directly from within Thunderbird. To do this, you have to download a plugin.

Note: At this time this is being written (Sep-2019), the Sieve plugin is flakey and has problems. The chief one is it's not compatible with current version of Thunderbird. The second is that the GUI doesn't offer a complete means of editing scripts. I strongly suggest using webmail until these issues are resolved.

To install the Sieve plugin into Thunderbird (you will only have to do this once):

• In Tools menu, select "Add-ons".

• In the left-hand pane, click on "Get Add-ons".

• On the right-hand side, click on "Browse all add-ons".

• In the search bar on the upper right area of the page, enter "Sieve".

• Click on the "+ Add to Thunderbird" button next to the Sieve plugin.

• On the permissions dialog box, click on "Install Now".

• In Thunderbird's "Tools" menu, select "Sieve Filter Settings...".

• For the Nevis mail server, in "Sieve Settings" select "Yes, manage Sieve settings for this account".

• Click "OK".

• Restart Thunderbird.

To use the Sieve plugin:

• Under "Tools" select "Sieve Message Filters..."

• Click on "managesieve" if it's not already selected, then click on the "Edit..." button on the right-side of the panel.

• You can edit the raw Sieve source if you wish, but you probably want to use the GUI editor to make sure your syntax is correct. If the "Source" button near the top left of the panel is highlighted, click on it to turn it off.