PurpleDrake fails on LG G3 (LG-D852)

I have a new LG-D852 (aka LG G3) running on Canadian provider Fido and I want to root it but PurpleDrake failed (running Linux):

Code:

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Waiting for device...  Found device!


Your phone is a [ LG-D852 ] on [ RGS ] running SW version [ V20d ] ...


Alright. We're ready to go. We're going to temproot your phone first. Press enter when you're ready!
Press [enter] to continue...

Rebooting phone...
Waiting for device... .................................... Found device!
Found device, checking if vulnerable...

ERROR: Your phone is not running a compatible software version. No vulnerable mode detected, rebooting phone.
We tried to temproot you, and it didn't work. This phone isn't vulnerable, it would appear.
Please post on XDA with your phone model, carrier, and SW version in the PurpleDrake thread and someone will take a look.
Your phone has been rebooted back to normal system mode, no changes have been made. Thanks for trying!

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Is there a better or more effective way to root the phone?