this is an important announcement to inform you about a severe issue with item calculations.
This issue affects all items that have both a discount and a tax rate set.
Details about the issue
Currently, item amounts are not calculated correctly if an item has both a discount and a tax rate set. The problem, reported by @mjmunger, is that amounts are calculated based on those two values. At the moment, the item taxes calculated are higher than they should be because of the way InvoicePlane calculates the amounts. Also, the item total are too high because of that.
All existing invoices created with items that contain both discounts and taxes must therefore be considered incorrect. I do recommend talking to your accountant on how to proceed.
Version 1.5.10 which will be released as soon as possible, fixes this issue. However, it will not modify any existing invoices. Existing invoices are legal documents that should not be altered after they are sent to the client. The corrected calculation method will be used for all invoices created after the upgrade.
Please update as soon as possible!
I deeply apologize for this issue. I was not aware of the real severity of the calculation problem and it should have been fixed way earlier.