Would it be possible to update to QT 5.12.12 or compile Qt for Manjaro with this patch?

Hi all, I hope this is the right place to ask, please tell me if I need to post a new topic elsewhere.

I’m experiencing this bug 375518 – global shortcuts do not work for non-Latin symbols of foreign keyboard layouts on the latest stable Manjaro KDE stable release (KDE version 5.88.0, QT 5.15.2)
It really impact my worflow using virtual desktops and global shortcuts to access it (eg: I can’t do Meta+2 shortcut on a FR keyboard layout, as 2 is é)

It seems to have been corrected in KDE current version, also in QT but not in 5.12.2.
I’m not really familiar with all this stuff. It’s been patched in QT 6 ([QTBUG-90611] Shortcut Alt+` is not working with non US layout - Qt Bug Tracker), I saw there is a newer version of QT available 5.15.12 (not in manjaro) but no idea if it had been included in this one.
Would it be possible to update to QT 5.12.12 if it’s patched in it ? Or would it be possible to compile QT for manjaro with this patch ? As I believe we are nowhere to KDE with QT 6, I really hope something can be done for all non US layout users.

Thank you very much for all your work.

Useful links:

Only for commercial clients, open source version is getting updates by KDE’s Qt5 Patch Collection. You should look up if KDE’s patch set contains this one.