Saving filters like custom actions

[ehrlacher]

I just stumbled across this discussion when I was looking for a way to save a filter (eg as/like an action) in this discussion

Removing fields without changing time stamp of unchanged files

In such a case I suggest to have a look at the action called "Remove fields except" There you can define which tags you want to keep (and therefore delete all other, however they are called). If you want to keep your embedded cover art, don't forget to include PICTURE in your list of tags to keep. Please test such a new action with some of your files to be absolutely sure that you keep ALL your tags wanted. A backup of your data is always recommended.

Maybe in this thread You can see why it could be very helpful/needful to have a filter saved, for it is "not trivial" (NOT ("$regexp($regexp($list('','','=='),'(.+?).+?==','$1~~'),'((ALBUM|ALBUMARTIST|ARTIST|COPYRIGHT|COMPOSER|GENRE|LYRICIST|MEDIATYPE|PICTURE|TITLE|TRACK|YEAR)~~)',)" IS "")) but You only need it temporarily to "clean up" Your data - so it is useful to have it stored inside mp3tag itself.

Of course at least 1 file have to be marked - but I see no showstopper in it.
I would like to heave it saved as an action like "Show only files with xxx (and then the filter string)"

Any ideas?