Status line with sum of selected move lines

I was sure this was discussed prior (perhaps in one of the mailing lists)…

Currently, there are many cases where summing of lines selected (debit/credit) is disabled, and it turns out in our practice that it is mostly off rather than on, which is rather infuriating.

Therefore, we would like to know where (what module/file) to force things to always have the status line with a valid selected/total debit/credit as well as add balance.

I believe I found it : Issue 3703: tryton: Show sum of all loaded selected records - Tryton issue tracker
I’ll try the patch provided… if it works okay, then I’m with Message 15798 - Tryton issue tracker

update: patch is unusable as is as the function was renamed and rewritten (probably for the gtk3 migration).
Somebody have something more current?