Magento 2.3 - After migration from 1.9 to 2.3 vendor/magento files missing

Question

After migration from Magento 1.9.2.3 to Magento 2.3.4 most of the files missing from vendor/magento.

But all the files located under app/code/Magento

Is this safe, shall i run my Magento 2.3.4 in this situation?

What about my future version upgrade?

Answer 1

Recently, I've upgraded from magento2.3.4 to magento2.4.0 and now all my files are in app/code/Magento and not in vendor/magento. I think they've updated 2.3.4 with the same as well. So, no problem, even now if you upgrade to 2.4.0, the directory would be app/code/Magento instead of vendor/magento. No issues, cheers!