ID 360613 - Registering a custom blend mode on startup sets the default Painting Mode to Paint Flow Vectors

Problem summary
Registering a custom blend mode on startup sets the default Painting Mode to Paint Flow Vectors

Customer reported version

3.4v1

Customer reported platform
ubuntu

Steps to reproduce

1) Install a startup script that registers a custom blend mode (or MEP)

2) Launch Mari

3) Open a Project

4) Notice that the default Paint Mode for the Brush is set to Paint Flow Vectors

Workaround
Unknown. 

Reproduced by support
Mari 3.4v1 - Windows 7, CentOS 7, OSX 10.12.4

Earliest version tested
Mari 3.3v1 - Last working version

Expected behaviour
Mari should set the default Paint Mode to 'Normal'

Actual behaviour
The default Paint Mode is set to 'Paint Flow Vectors'