Problem with houndeyes

So a while back I noticed that my houndeyes did not have the constant “glow” on their backs and appeared only when attacking. I have no mods, I have re-installed the game multiple times and nothing changed.

I am very confused with this and any help would be appreciated!
I will leave some specs here in case its any help.

OS Name: DESKTOP-PUDSU4Q
System Manufacturer: Acer
System Model: Aspire V3-771
System Type: x64-based PC
Processor: Intel® Core™ i5-3230M CPU @ 2.60GHz, 2601 Mhz, 2 core(s), 4 logical processors
Installed Physical Memory (RAM): 8,00 Gt

This feature has been removed, I remember, maybe will come back in Xen update?

@chenmozx thanks for telling me that! I was a bit bothered with that but it is good to know that it was normal.

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