We received a report Terrestria wall signs break as oak wall signs in 1.18.2 and after some investigation found this happens when using Quilt (loader 0.17.4, QFAPI 1.0.0-beta.24_qsl-1.1.0-beta.26_fapi-0.58.0_mc-1.18.2) but not with any Fabric version I can find. No related problem seems to be logged.

I have also reproduced the problem with QFAPI 4.0.0-beta.11_qsl-3.0.0-beta.15_fapi-0.60.0_mc-1.19.2.

Our loot tables are produced via datagen and here are examples (first a standing sign, which works correctly in Quilt, and then a wall sign, which breaks as an oak sign):

redwood_sign.json

{
  "type": "minecraft:block",
  "pools": [
    {
      "rolls": 1.0,
      "bonus_rolls": 0.0,
      "entries": [
        {
          "type": "minecraft:item",
          "name": "terrestria:redwood_sign"
        }
      ],
      "conditions": [
        {
          "condition": "minecraft:survives_explosion"
        }
      ]
    }
  ]
}

redwood_wall_sign.json

{
  "type": "minecraft:block",
  "pools": [
    {
      "rolls": 1.0,
      "bonus_rolls": 0.0,
      "entries": [
        {
          "type": "minecraft:item",
          "name": "terrestria:redwood_sign"
        }
      ],
      "conditions": [
        {
          "condition": "minecraft:survives_explosion"
        }
      ]
    }
  ]
}

I've finally developed a better understanding of this issue and the difference between Quilt and Fabric is more along the lines of different order of initialization. In other words, this is not a Quilt bug but rather it was a bug in our mods which showed up differently in Quilt.

In case anybody else runs into this, wall signs of either type do not really work with loot tables anymore. It is necessary to use blockSettings.dropsLike(standingSign) instead.