Series with group-deleted chapters don't trigger the "there's a skip in the middle" message

[Varrel]

Not really sure if this is a bug, but I would consider it an oversight.
https://mangadex.org/title/22581/saguri-chan-tankentai
When you try to go to next chapter from 26, you get

There seems to be a gap between the current chapter and the next available one (Vol. 3 Ch. 26 → Vol. 4 Ch. 35). Click here to continue.

https://mangadex.org/title/21599/ragna-crimson
You don't get that when you go from ch 1 to 3, where 2 was taken down.

I doubt this would happen much anymore, but it would be nice if this got futureproofed.
(EDIT: Maybe this only happens if you have show deleted chapters toggled?)