/fill coords coords block of choice replace block of choice

to give an example this is what happens when i do that syntax which i am used to until 1.17 changed it in some way that i dont know:

/fill 1123 64 1178 1199 64 1138 minecraft:air replace minecraft:shroomlight

this is what shows up in 1.17.1

/fill 1123 64 1178 1199 64 1138 minecraft:air replace minecraft:shroomlight

what was changed?