Minecraft: 1.16.5
Forge: 36.2.0

Noticed these errors in my latest.log, wondering if it's anything to worry about?
"[Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category:" xyz

unlikely
(why is this on the apoth tracker?)

Ah, yeah no those don't do anything, the recipe book doesn't pick up on modded stuff and it tends to whine about it. Didn't realize there was a link in that original post

unlikely (why is this on the apoth tracker?)

Because of these warnings for Apotheosis?

[30Sep2021 19:51:58.399] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/diamond_mining_arrow
[30Sep2021 19:51:58.399] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:player_activation_range
[30Sep2021 19:51:58.399] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/spectral_arrow
[30Sep2021 19:51:58.400] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:spawn_range
[30Sep2021 19:51:58.400] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:inverse
[30Sep2021 19:51:58.401] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/obsidian_arrow
[30Sep2021 19:51:58.401] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:spawn_count
[30Sep2021 19:51:58.401] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:max_delay
[30Sep2021 19:51:58.402] [Server thread/INFO] [net.minecraft.server.MinecraftServer/]: Saving chunks for level 'ServerLevel[New World]'/minecraft:overworld
[30Sep2021 19:51:58.402] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:min_delay
[30Sep2021 19:51:58.402] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:redstone_control
[30Sep2021 19:51:58.402] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:max_nearby_entities
[30Sep2021 19:51:58.402] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:ignore_spawn_cap
[30Sep2021 19:51:58.402] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/iron_mining_arrow
[30Sep2021 19:51:58.403] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:require_players
[30Sep2021 19:51:58.403] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:ignore_spawn_conditions
[30Sep2021 19:51:58.403] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:spawner_modifiers/apotheosis:spawn_eggs
[30Sep2021 19:51:58.403] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/broadhead_arrow
[30Sep2021 19:51:58.404] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/explosive_arrow
[30Sep2021 19:51:58.404] [Render thread/WARN] [net.minecraft.client.util.ClientRecipeBook/]: Unknown recipe category: apotheosis:fletching/apotheosis:fletching/arrow