Can one amend a git commit message using IntelliJ, or should one resort to command line?
How can this be done please?
Commit messages can be edited during a rebase. Invoke the Rebase command from the VCS menu, confirm the branch settings, then click the Rebase button. You'll be presented with a list of your unpushed commits. Choose the reword action from the drop-down to the left of the message you want to edit.
Check the git doc on Rewriting History for details on other rebase actions.