Choose from:
(1). Click on view filter from thunderbird section if you want to change your filter cover. Check that the filter cover covers all active updates..
(2). Name the filter to make it easier to recognize. If it's for spam name it spam, if it's emails from a certain person, put their name in the name field..
(3). It's the first option, and it has 3 lines , 4 spaces, and 2 circles. Use the big arrow to look at one of the empty lines at the top of the screen..
(4). Click " save as..." Right click on the same filter and then click save as. Go to the " filters " window on your xp, compared to the normal filter settings tab and see your thread message..Choose from options above and answer: What most naturally follows?

How to make a message filter in mozilla thunderbird
In thunderbird, click on tools.
Click on message filters.
Click on new filter.
Answer:
(2).