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How to show product on-hand/forecasted/available quantity in invoice line?
*I don't use Sale module / sale order/quotation.*
I use Stock picking from invoice module.
https://apps.odoo.com/apps/modules/13.0/invoice_stock_move/
Odoo 13 community edition.
Inventory is not linked with invoices
You need customization module, contact me on hassan@mast-it.com if you need some one do it for you
1. Use the live chat to ask your questions.
2. The operator answers within a few minutes.
This needs customization. Providing your code will enhance your chances for help.