Easy. Polyploidy, common in ferns (Dryopteris spp) and other plants (Solidago canadensis complex) etc.
Duplication of segments of chromosomes
Duplication of whole chromosomes.
And so on.
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Sorry, but you didn't answer my post.
I know that DNA is very adapt at making copies of itself.
Your knowledge is vast, but you are using it to try to dazzle me and avoid my request.
Wrong. You started out advocating the notion that mutations diminish the information in the genome.
I demonstrated that was not so, which you more or less acknowledged.
Then you wanted examples of increasing the information by mutation.
I mentioned a couple of items that I remember teaching in a basic college biology class. If it happens you didn't learn it, why not try google? Or ask politely?