Capacitive buttons, navigation bar and PIE control

Hi guys,

Ok, so I'm coming from an old Nexus 4 on which I was used to do everything with one hand (right).
I was used to Pie Control, and completely remove my software navigation bar (qemu.hw.mainkeys=1 in build.prop)

Now, I'd like to do quite the same thing with my OP3, but I'm struggling a bit.
As you know, with OOS, we can use either:

1. Capacitive Buttons


2. On-screen navigation bar

When I use Pie Controls (either LMT or GravityBox) and set the navigation to capacitive buttons, it's mostly OK, but there's always the unintentional touch, especially when holding the device in landscape mode.
When I set the navigation to on-screen buttons (but don't use them), "Back" and "Home" simple tap on Pie Control doesn't work at all (Longpress's and Recent simple tap work fine, though).
I tried fiddling with build.prop but didn't manage to disable both altogether.

Code:

---

# enable navigation bar
#ifdef VENDOR_EDIT
#liuhuisheng@framework disable navigation bar
#qemu.hw.mainkeys=1
#else
qemu.hw.mainkeys=0
#endif

---

Anyone knows how to disable both capacitive buttons AND standard software navigation bar ?
If it's possible to stay on OOS for the moment, that would be great :)

Thanks in advance.