Create WebMapServiceCatalogItem with code (probs : supportsSplitting, supportsOpacity)

[Maxime2023]

Hello, actually i modified terriaJs, to avoid the use of the json products file, and better use an api which sends me all the data i need. In the v7 version i did it and everything worked correctly, but since the v8, i have a problem with the compare option : my data doesn't move by side and i also have a problem with the opacity cursor which doesn't show and i don't understand why, i added these two elements : {supportsSplitting: true, supportsOpacity: true}.
I created a WebMapServiceCatalogItem with only code by calling it inside my component, then i used the function setTraits(), to add a name, layer, opacity, url... Exactly like the json config file and finaly i added it to the workbench with the function add(). But the Opacity section doesn't show and the split doesn't work (i can choose left or right but the layer doesn't move).
Can someone help myself ?
Thanks.