### Preconditions <!--- Provide a more detailed information of environment you use --> <!--- Magento version, tag, HEAD, etc., PHP & MySQL version, etc.. --> 1. Magento MSI 2. Virtual and Downloadable products created 3. Additional Source created ### Steps to reproduce <!--- Provide a set of unambiguous steps to reproduce this bug include code, if relevant --> 1. Open one of these products to edit in admin 2. Click button "Assign Sources" 3. Select new Source to assign 4. Click button "Done" 5. Set Qty for this new Source 6. Click button "Save" ### Expected result <!--- Tell us what should happen --> 1. Product has to be saved 2. New Source has to be assigned ### Actual result <!--- Tell us what happens instead --> 1. Exception message "Could not save Source Item Configuration" 2. New Source is not assigned
