Spawners tick without setting mobs

Help for Reproduce

1. Get Spawner

   give @s spawner
   

2. Show Delay

   scoreboard objectives add var dummy
   scoreboard objectives setdisplay sidebar var
   execute store result score temp var run data get block <Spawner BlockPos> Delay
   

Behaviour

I'm not sure which one were intended but they should conflict:

• No flame particles indicate they're active (client side
• Delay are in reducing-resetting cycle shows they're actually active (server side