you can already filter on address. http://kb.mozillazine.org/Filters_%28Thunderbird%29

BTW my spam goes to a junk folder, not deleted.

Thanks for your response, Matt, but it does not address my question. . I am using filters and the spam goes to the folder 'delete'. Most of the time I can delete everything, but sometimes a real email comes in this folder. It is time-consuming and prone to errors to view this folder and find the real emails between the spam. . Today there were 27 spam messages in the folder 'delete'. What I would like is the following functionality. 1. I select all messages. 2. I click a button or right-click the mouse. 3. I select the option 'put messages in filter'. 4. I select the right filter, for example 'DELETE', which immediately deletes the emails. 5. A function gathers all email-addresses in the from-field of the messages to create filter-rules like 'FROM contains'. 6. Another function gathers all url's in the body of the messages to create filter-rules like 'BODY contains'. (Most spam wants you to visit websites, no sane person would ever visit. Specially websites with .ru as country-code.) 7. You check the list of new rules, remove undesirable rules and then click 'ADD to filter'.

With such functionality it would be save to delete the messages without reviewing.

You issue is your using filters to tackle a problem that can not be adequately managed by filters. That is why Thunderbird has a Bayesian spam filter. Because it has to learn and adapt over time. Hand crafted filers for that purpose are a poor investment in time and while they may offer some feelings of fulfillment in that you have fixed their little red wagon.

Ultimately you spend more time fiddling with filters which eventually becomes complex that they actually fail to interact nicely with one another than you would manually dealing with the spam in the first place.

I look in the spam folder perhaps twice a year when I remember there is one. Not because I am busy, because there is no point. Thunderbird manages about 99.9% of my spam and has not had a false positive in years. Just the odd miss for which I click the spam button and it is gone.

Compare that to what your doing. I am sure it takes more that a second or two a day. Your probably taking longer than that to review your deleted folder.

So why are you not using the learning filter? and educating it on your choices. It doe take about 50 spam and not spam choices for it to start getting with the program. But it works like a charm for me and with application would for you to. Perhaps your desire for changes to Thunderbird is driven by a use case that is not optimal. Have a look here to get some good information on how Thunderbird's built in junk filtering works.

Thanks for your input, Matt. I will try it out.