https://www.dndbeyond.com/sources/dnd/ottg/locations#CoastalHighlandsWanderingEncounters

Singing Harpies links to dnd core rules harpies instead of the Obojima harpies. Correct link would be https://www.dndbeyond.com/monsters/5322012-harpy-obojima

https://www.dndbeyond.com/sources/dnd/ottg/locations#AHAHQAdventureHooks

"Coaster Divers' Lodge" should be "Coastal Divers' Lodge"

https://www.dndbeyond.com/sources/dnd/ottg/locations#TheShallowsWanderingEncounters

Encounter 1, "fishfolk" should be "fish folk"

https://www.dndbeyond.com/sources/dnd/ottg/locations#TheShallowsWanderingEncounters

Encounter 9, links to the Corruption do not work

https://www.dndbeyond.com/sources/dnd/ottg/spells-potions#DragonFrogTransmutation

"Ancient Dragon Frog" should be "Elder Dragon Frog"

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#Demon

Spirit Realm link doesn't work. Should be pointed to this https://www.dndbeyond.com/sources/dnd/ottg/about-the-world#SpiritRealm

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#DragonFrog

Nakudama link doesn't work. Should probably be pointed to https://www.dndbeyond.com/sources/dnd/ottg/player-options#Nakudama

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#FishFolkinGeneral

The two links to the Shallows and the Corruption do not work. 

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#HillDragon

Neither of the links in this section work either.

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#HistoricPast

The two links here are similarly broken.

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#PrideandPrejudice

The link to the coastal highlands is broken here.

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#PostalKnight

The links to Courier Brigade, Yatamon, and Gale Fields are all broken here.

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#SeaweedElemental

Link to the Shallows is broken.

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#SkeletalFish

Link to the Corruption is broken

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#SkeletalFish

Link to Society of Young Stewards is broken.

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#OrangeSlimes

Link to Mount Arbora is broken

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#CorruptedSlimes

Link to the Corruption is broken

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#Spirit

Link to Spirit Realm is broken

https://www.dndbeyond.com/sources/dnd/ottg/friends-foes#Stul

Gift of Shuritashi and Mount Arbora links are both broken here.

Honestly, seems like every single link on the Friends and Foes section is broken. They're all pointing to the Friends and Foes section instead of the appropriate chapter.