Filter for titles

Good day,

I have searched but not found.

I would like to have a filter for having all titles beginning by the letter D.

How to mange this please ?

Thanks

Try
%title% MATCHES ^D

Perfect

Where I could find these type of info in help topic ?

Thank you for your usual help

I think here:
http://help.mp3tag.de/main_filter.html
(or if you use the F1-option locally: Topic Filters).

Please note that the keyword "MATCHES" expects a regular expression afterwards. The help topic links to the parameters.

In your case I used the ^ as this means "Beginning of string".