Crash when using inline slot_source inside any command

Hello, I was just messing about trying to learn In-Line slot_sources and was trying to delete an item in a specific slot with a specific name like this:

/give @s stick[custom_name="Test"]

/item fill entity @s {"type":"filtered","item_filter":{"predicates":{"custom_name":{"text":"Test"}}},"slot_source":{"type":"slot_range","slots":"hotbar.*"}} with cake

(This should replace all of my hotbar slots that have a item named Test and turn them into cake)

P.S. Why can we not check the name of the item as a regular string or list of strings?? Why does it have to be a compound only?

Steps to Reproduce:

1. Load a world in 26.3 Snapshot 4, 5, 6, or 7.

2. Attempt to evaluate or pass an inline a slot_source object (e.g. inside a command block or chat command using inline minecraft:slot_source) like this /item fill entity @s {}.

3. Notice the game crashes immediately.

Observed Result: The game crashes upon evaluating any inline slot_source structure.

Expected Result: Inline slot_source objects should parse and resolve correctly as introduced in the Snapshot 4 technical changes.