Thanks for your answer, ikm.
I'm not sure if I'm able to recompile the source code, but I'll try it.
The scrolling won't be a problem, because I only need the history file after using GoldenDict to see what vocabulary I was looking for while reading texts.
At the moment I use a little batch-file:
type history. >> merge.txt
At the end I delete the duplicate lines.
That'll do for me. It's only a little amateurish.
Once more thanks for the program and your work.