Whenever the greenhouse multiblock formed, it always has this problem:

even though there's no block on the roof

I test this in both survival and creative world

Mod version:
gregtech-1.12.2-2.4.4-beta
GregTech+Food+Option-1.12.2-1.8.2

(I'm not good at English, sorry)

So, I found some new problems(I guess):
First, when I build the multiblock, the problem appears, even though there is no block on top of it . If I run a recipe, the problem disappeared
Second, the problem will appear if the time is night or the weather is rain
Third, TheOneProbe always display same progress bar, whether the multiblock has problem or not

Also, this is my test world:
Gregtech Test World.zip

Full mod list:
!mixinbooter-4.2
_bansoukou-4.3.1
CodeChickenLib-1.12.2-3.2.3.358-universal
GregTech+Food+Option-1.12.2-1.8.2
gregtech-1.12.2-2.4.4-beta
GregicalityMultiblocks-1.12.2-1.1.5
HadEnoughItems_1.12.2-4.23.0
loliasm-5.6
topaddons-1.12.2-1.13.0
theoneprobe-1.12-1.4.28

I used the creative terminal to buld the greenhouse, so there is no extra block on top

It appears you may have some extra frames on the top of the multiblock; perhaps removing those would fix it.

Try running a recipe in it; does that fix the issue?

It's still running, but it's take much longer to run

Actually, it seems fine; could you send me your world's files?

I am still unable to replicate the issue when it is daytime and not raining. I will modify its tooltip to make it clearer that it runs more slowly at night, and make it run as it rains.

I found out that TheOneProbe and GT scanner have the same progress displaying bug
For example, I build a greenhouse multiblock with 1 iv energy hatch and run this recipe:

When I run the recipe without the warning, it takes 12.25 seconds to run the recipe, TOP and GT scanner also show that too

If the warning appears, it takes 25 seconds to run the recipe, but TOP and GT scanner still showing 12 seconds

I am sorry to interrupt you.
The TOP's display time does not change, but I feel like the speed of the progress bar seems to have increased by 0.5 times.

Although the greenhouse is supposed to run twice as slowly without adequate sunlight, I should probably try to get it to show this.