Ok, I see. I upgraded from 2009 version. There I used "\s+$" to match end of line wihtespace. I see now that that "+" is already included there. As you say, it still should not lock up because of my error.
And I just noticed that it went into a long spin when I pressed Ctrl+Shift+F, probably 8sec.
As extra info: I am running on a corporate PC where some directories have read-only access. I do not know if this makes a difference, but I had some problems with 2009 because of this. I do not remember the exact details, I had to explicitly provide the write access to some dir, and repoint some cache or temp file to a different location.