How can I see celestial cards in the deckbuilder?

Topic.

You will never see them in deckbuilder since deckbuilder is only for collectible cards and celestial cards are by definition not collectible.

If you are wanted to peruse them, they are in the card library as Targon cards. You could go here: https://outof.cards/legends-of-runeterra/cards/?region=targon&rarity=7

If you were just trying to figure out if it is worth including Invoke cards into your deck: the answer is probably "yes" -- they seem quite successful.

You can also see them in the client under the “special categoriess” section of the card search menu thing. It’s under the part where you can filter cards by expansion.

Thx.

FYI. It was added.

The game keeps updating. I think they're doing hot fixes.