When trying to add blocks to a vanilla tag, original tag gets overridden. Ignoring the "replace" value in the json. This value can be set to true/false or missing, makes no difference.
For example:
My logs.json in data/minecraft/blocks/
{
"replace": false,
"values": [
"#nom:cinnamon_logs"
]
}
My own logs do get added but the vanilla ones lose the tag:

This is on forge 1.14.2-26.0.32
Is it working on forge 1.14.2-26.0.23 ?
It does not.
Then it is most likely not connected to the inverse tags
Adding to the vanilla tags works, but it overwrites the existing ones:


Without the logs.json :

I was able to reproduce this, it is not a tag issue. It is a resource manager issue. Something messed up and any extra resource packs added override the vanilla one. I'll look into it tomarrow.


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