Form components :disabled styles not working with Material Theme and inputVariant: "filled"

[adamshafer]

Hello. We are working on transitioning our project from PrimeVue v3 to PrimeVue v4. We are looking to use the Material theme with inputVariant: "filled" to mostly mimic the custom styles from our v3 project. I noticed that the disabled fields do not have a different background color, and are not styled to look disabled. This problem only seems to happen with the Material theme, and looks fine with Aura/Nora/etc.

Example:
https://stackblitz.com/edit/pet94w8j

It looks like the issue here is that the background CSS for .p-inputtext.p-variant-filled is being applied, when it should be applying the .p-inputtext-disabled style:

This is not specific to the InputText component, and appears to be an issue on all disabled form components (except maybe Checkbox).

Any assistance here is appreciated, and let me know if this belongs in the PrimeVue repo. I believe this is a primeuix issue.