Amazing looping tool. It will be ideal for external instrument tracks, guitar, bass.
https://sourceforge.net/projects/loopauditioneer/
https://sourceforge.net/projects/loopauditioneer/
Make sure to search to see if your idea has been posted before! Check our issue tracker as well, just to make sure you are not posting a duplicate: https://github.com/LMMS/lmms/issues