I found that it's not a bug of Freemind, some java look&feels do not support ctrl+up in Freemind, like 'nimbus' and 'quaqua'. change another look@feel can solve this problem.
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I found that it's not a bug of Freemind, some java look&feels do not support ctrl+up in Freemind, like 'nimbus' and 'quaqua'. change another look@feel can solve this problem.