[Bug]:

[Mithun1258]

[Bug]:

[tomaszjhuczek]

I tested the latest version from Modrinth as well as compiled my own version from source. I can confirm that dragon roosts and caves spawn normally albeit they are really rare (possibly intentional?) and also can confirm that this is not a bug (unless the structure generation rate is unusually low, then it possibly is) in both versions. Dragon nests will not spawn in forest biomes normally by default as well (this can be changed in the configs located in config/iceandfire).
If you believe that dragon nests are too rare, I recommend changing the following settings in iceandfire-common.toml:
"Dangerous World Gen Dist Separation" = 300 (Lower number, smaller distance between nests/other dangerous structures)
"Generate Dragon Cave Chance" = 180 (Lower number, higher chance of a dragon cave generating)
"Generate Dragon Roost Chance" = 360 (Lower number, higher chance of a dragon roost generating)

Extra info: Environment used for testing

Minecraft Version: 1.20.1
NeoForge Version: 47.1.106
Ice and Fire Version: 2.1.13-1.20.1
Citadel Version: 2.5.4
Other Mods Installed:

• BiomesOPlenty-1.20.1-18.0.0.598
• TerraBlender-forge-1.20.1-3.0.1.7