PS4 shader compile error in 'Triangle Core.cginc'

Hi,

We're getting a shader compiler error on PS4 on lines 134-136 of 'Triangle Core.cginc':

Shader error in 'Shapes/Triangle Darken': Program 'vert', incompatible argument list for call to 'mul'. Found 1280 possible candidates: at Assets/Thirdparty/Shapes/Shaders/Core/Triangle Core.cginc(134) (on ps4)

The cause is three attempts to multiply a half3x3 by a half2 - the PS4 shader compiler is stricter than the other platforms on mismatched calls like this, and throws errors instead of attempting to guess the right thing to do.

// 2D miter offset directions
half2 miterVecA = GetMiterOffsetDirFast( nCA, nAB, padding );
half2 miterVecB = GetMiterOffsetDirFast( nAB, nBC, padding );
half2 miterVecC = GetMiterOffsetDirFast( nBC, nCA, padding );

// add local space padding
half3x3 mtxProjToLocal = transpose(mtxLocalToProj);
a += mul(mtxProjToLocal, miterVecA);
b += mul(mtxProjToLocal, miterVecB);
c += mul(mtxProjToLocal, miterVecC);

I'm not clear on the right fix for this - what is the intention here?

Thanks,

Keith