Advanced featuresActions
Actions allow you to use all the power of the Unix command-line with your emails. You can define various commands, taking parameters such as the current email file, a list of emails, the currently selected text, and so on. In this way, you'll be able to perform various tasks such as editing a raw mail in your text editor, "hide" what you mean using ROT-13, apply patches contained in emails directly, and so on. The only limit is your imagination. You can configure Actions via the Tools menu.
Simple Open With...Menu name: Open with/kate Command Line: kate%pOpens the file of the selected decoded MIME part (%p) with the kate text editor.
Spam management using BogofilterMenu name: Bogofilter/Mark as Ham Command Line: bogofilter -n -v -B "%f"Marks the currently selected mails (%f) as 'not spam' using Bogofilter.
Menu name: Bogofilter/Mark as Spam Command Line: bogofilter -s -v -B "%f"Marks the currently selected mails (%f) as 'spam' using Bogofilter.
Search google using an external scriptMenu name: Search/Google Command Line: |/path/to/google_search.plSearches google for the currently selected text (|) using the external script google_search.pl.
Templates
Templates are used in Composition windows, and act as a model for emails. Templates can be filled with static text and dynamic parts, such as the original sender's name ("Dear %N, ..."), the date, ... When applying a template, the dynamic fields will be replaced with the relevant values. You can configure templates via the Tools menu.
Processing
Processing rules are the same as Filtering rules, except that they are applied when entering a folder and apply only to this folder. You can use them to automatically move old mails into an archive folder, or for further dispatching of emails. You can set each folder's Processing rules by right-clicking on it.
Processing rules are accompanied by Pre-processing and Post-processing rules. Like Processing rules, they apply only when opening a folder, but like Filtering rules, they are shared accross all folders. You can configure them from the Tools menu. Pre-processing rules are executed before the folder's specific Processing rules, while Post-processing ones are executed after.
Plugins
Plugins are the mechanism of extending Sylpheed-Claws' capabilities. Imagine that you want to store your mails in a remote SQL database. In most mailers out there this is simply impossible without reworking the internals of the mailer. With Sylpheed-Claws you can simply write a plugin to achieve the task.
This is just an example of the possibilities. A good number of plugins developed for Sylpheed-Claws already exist, and more are to come. The Extending Sylpheed-Claws section gives details of them.
Hidden preferences
There are a number of hidden preferences in Sylpheed-Claws, preferences that some users who we wanted to please couldn't live without, but which did not have a place in the GUI in our opinion. You can find the following, and change them while Sylpheed-Claws is not running in ~/.sylpheed-claws/sylpheedrc.
bold_unreadshow unread messages using bold font in summary viewcolor_newcolour (as hex triplet) of folder name when indicating new messagescache_max_mem_usagethe maximum amount of memory to use to cache messages, in kB.cache_min_keep_timethe minimum time to keep a cache in memory, in minutes. Caches more recent than this time will not be freed, even if the memory usage is too high.enable_hscrollbarenables horizontal scrollbar in summaryviewenable_rules_hintenable alternate lines in GtkTreeViewsenable_swap_fromdisplay sender's email address in To column in Sent folder instead of recipient'sfolderview_vscrollbar_policyspecify the policy of vertical scroll bar of folder viewhover_timeouttime in milliseconds that will cause a folder tree to expand during drag 'n' drop when the mouse cover is held over itstatusbar_update_stepupdate stepping in progress barstextview_cursor_visibledisplay the cursor in the message viewthread_by_subject_max_agenumber of days to include a message in a thread when using 'Thread using subject in addition to standard headers'toolbar_detachablehide handles in the toolbarsutf8_instead_of_locale_for_broken_mailuse UTF-8 encoding for broken mails instead of current localewarn_dnddisplay a confirmation dialog on drag 'n' drop of folders