From: Junio C Hamano <hidden> Date: 2016-06-15 22:42:07
Yasushi SHOJI [off-list ref] writes:
first, create new branch at where you wanna change the message
git checkout -b temp HEAD^^^ # hmm... HEAD^3 doesn't work
Because it should be spelled HEAD~3. HEAD^3 is "the third
parent of HEAD" and usually does not exist, unless you are
talking about an Octopus merge of three or more branches.