My first time using git with VSCode I had the experience of the file changes showing up in the Source Control even without saving them although now that doesn't happen anymore unless I manually save the modified file and that's when it appears in the 'Changes'. I haven't changed any settings/configuration and I'm not sure if manually saving a file within the repo in VSCode might've had an effect because I remember doing that before pushing and closing the editor.
I'd like to expand on this issue by detailing the previous behavior of my VSCode. After cloning a remote repo, git would automatically detect changes in existing files even though they haven't been saved yet although when a new file is added (say a text file) it had to be manually saved first and from then on Source Control would detect any changes to that file without having to save it.