Breaking a lead that is attached to a fence doesn't trigger minecraft:on_unleash

In developing an add-on, I’ve discovered that when breaking a lead that is attached between an entity and a fence post, the minecraft:on_unleash event trigger is not activated.

Here is the relevant code I’ve been using to test this:

[.....]
        "minecraft:leashable": {
          "on_leash": {
            "event": "omb:leash_combo",
            "target": "self"
          },
          "on_unleash": {
            "event": "omb:unleash_combo",
            "target": "self"
          }
        },
[.....]
      "events": {
        "omb:leash_combo": {
          "sequence": [
            {
              "trigger": "minecraft:on_leash"
            },
            {
              "trigger": "omb:on_leash"
            }
          ]
        },
        "omb:unleash_combo": {
          "sequence": [
            {
              "trigger": "minecraft:on_unleash"
            },
            {
              "trigger": "omb:on_unleash"
            }
          ]
        },
        "omb:on_leash": {
          "queue_command": {
            "command": "tag @s add leashed"
            }
          },
        "omb:on_unleash": {
          "queue_command": {
            "command" : "tag @s remove leashed"
          }
        },
[.....]

With this code included in my add-on, the tag “leashed” is applied whenever an entity has a lead attached to it. The tag persists until the player personally removes a lead from the entity.

If the player hitches the entity to a fence and then breaks the lead, the “leashed” tag is not removed. The player is forced to re-attach a lead to the entity and then break it directly.