Steps to reproduce:

1. Download and import attached project. (NegativeScale_THIRD_TRY.zip)
2. Open scene: test_3_Cubes
3. Press play.

Expected result: Middle particle looks the same as the left particle.
Actual result: Particles with Standard (and probably more) shaders are not scaled correctly, their quads are inverted individually.

On 5.3*, 5.4.0b2 and earlier different behavior is seen, because mesh scale did not worked before at all.

Reproduced on: 5.4.0b21