I found a little bug in Renoise v2.50 about “Clone Current Pattern”. For example :
1°) In the Pattern 00, I edit notes and I use the “Clone Current Pattern” option to the patterns “01”, “02” and “03”.
2°) OK, it’s working, no problem.
3°) Now, I kill Patterns “01”, “02” and “03”.
4°) In the Pattern 00, I use the “Clone Current Pattern” to one only pattern.
5°) It’s working BUT I am sorry : the clone pattern is working to the pattern “04” directly whereas the patterns “01”, “02” and “03” aren’t used !
You are not deleting the pattern from the song, you are just deleting (cutting) it from the pattern sequence. The pattern still exists because you might want to use it at a later position in your song. If you want to completely delete unused patterns from your song, use the “Sort & Delete Unused Patterns” feature. (Or do as vV suggests)
I say this as politely as I can, but please spend more time reading the manual and other forum posts before you start new threads. A lot of the ‘bugs’ you have reported lately are not bugs at all, but simply come you from not fully understanding how something in Renoise works.
Yes, it is working if I use “delete unused patterns” before using “Clone Current Pattern” (step 5). It is strange that it is working because my patterns “01”, “02” and “03” are empty and aren’t in the sequencer window.
maybe you should look closer to the previous posts… 
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