Question Artifacts on particle strips when changing the size over lifetime

Hello !

I have a "simple" problem on this example :


I have a simple stretching particle strip with a custom shader to create some motion in it, and I also use a "Set Size over Lifetime" node in my Output context, to make the trail thiner toward the end of its lifetime and get a nice movement effect on my projectile.

But as you can see, there is kind of "zig-zag" at the end of the trail, which happens only when I use Size over Lifetime. It's something that happen on any trail that had a change of size over its lifetime. I have avoided the problem on some of them by directly making my trail thiner in the texture, but not only it's annoying if I want to adjust it and test different results, it's also impossible to do with tiling/repeating textures (like the one in the image above).

Do you have any idea about what can cause this and how to solve it ?

Thanks !