COMMIT_EDITMSG is a file which VSCode opens when you do not provide commit message in the Source Control plugin box –
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The COMMIT_EDITMSG file looks like this –
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Here you can write your commit message at the top.
If you don’t want this file to open up, you can turn the setting off in VSCode from here –
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Uncheck Use Editor As Commit Input
setting and the file will not open anymore. You can find this – Settings -> Extensions -> Git
You can also use command line git.useEditorAsCommitInput
to turn it off.