Why is there a d in fridge but not in refrigerator?

So you would ask this very question.

I was going to write a synopsis of this article, but it just went on and on and I couldn't tell which were the important bits. So here's the info to read for yourself.

https://www.merriam-webster.com/words-at-play/fridge-vs-frig-spelling-short-for-refrigerator#:~:text=The%20word%20we%20pronounce%20%5CFRIJ,early%20uses%20were%20spelled%20frig.

I think there used to be, but it sort became left behind over time. Poor little letter 'd'.