Previewing GRAY clips with _Matrix property fails

[Former user]

When trying to preview clips of the color family vs.GRAY which have the _Matrix property attached to them, VSEdit throws this error:

Error on frame 0 request:
Resize error 1026: GREY color family cannot have RGB matrix coefficients

This happens despite the script evaluating fine. VapourSynth Multi-Viewer previews the clip without any problems as well.

Code for reproduction:

import vapoursynth as vs
core = vs.core

red = core.std.BlankClip(format=vs.RGBS, color=[1,0,0])
xyz = core.resize.Bicubic(red, primaries_s="xyz", primaries_in_s="709", transfer_in_s="linear")# this attaches the matrix frame property. 
y = core.std.ShufflePlanes(xyz, 1, vs.GRAY)
#y = core.std.SetFrameProp(y, "_Matrix", True)
y.set_output()

Deleting the matrix frame property resolves the issue.