[V5.1 - Ground Combat] Alien hidden movement screen doesn't disappear, aliens never end their move

[EvilCactus]

I was playing ground combat with Sebillians.

1) one of the aliens (with a shield) appeared and the soldier's reflexes triggered, he shot first from a shotgun;

2) then the alien made another one-two steps and the same soldier's reflexes triggered again, the alien died;

3) then the aliens 'hidden movement' screen appeared and never gone.

The save file is attached.
I had to skip the first Terror Mission because it gets stuck on 99% loading. So the bug appeared in the next mission after this one.

Initialize engine version: 5.5.6f1 (3fb31a95adee)
Direct3D:
    Version:  Direct3D 11.0 [level 11.1]
    Renderer: NVIDIA GeForce MX150 (ID=0x1d12)
    Vendor:   NVIDIA
    VRAM:     1983 MB
    Driver:   26.21.14.3039

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