@ckubs The error "The following untracked working tree files would be overwritten by merge:" indicates that between the time that you last upgraded, and now, you have made some changes to the files in that list, and so the git command will not complete and you are not being upgraded. Have you been making changes to the Latvian translations? The best way to do that is through the Transifex localisation tool, and not by changing the public/language/lv files directly.
The easiest fix for you, if you are happy to lose your changes, is to simply delete all the files that the error is complaining about. If it's only the Latvian files, then you can do 'rm -rf public/language/lv' and they will be gone.
Alternatively, you can keep the Latvian files in another directory by doing 'mv public/language/lv public/language/my-lv'.
Once the files are no longer in existence, after you do one of the previous steps or something similar, retry the upgrade procedure!
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