Odoo shows only one type of taxes on out_refund tax lines, but should be more there

Question

Client refunds (out_refund) show only one type of Tax in the tax list, even if there should be more than one. For example: I have this out refund lines: One S_IVA10B and other with S_IVA21B

You can see S_IVA21B and S_IVA10B, right? Well... if you go to Other information tab, you find only one tax line:

Any of you know why this is happening (only) on refunds? The out_invoice elements are correct.

Answer 1

It was a reported bug. Now it is solved in this commit: https://github.com/OCA/l10n-spain/commit/4ac7266648aab0fa469ae271a7541f6bec79f3fb For unknown reason it haven't worked for me, but there is an official fix.