Highest gear skipping after new chain. Is it too long?

Hi everyone, hope you can point me in the right direction. Somewhere over the winter I swapped in a fresh chain on my 12 speed 51T. I remember just putting the old and new next to each other, taking the length of the old one as reference.

Now that I am trying it out it seems like the highest gear is skipping, even when pedaling very lightly. Does the chain look too long? There is definitely some tension on the derailleur. I tried fiddling with the adjustment but nothing seems to make it better.