Game Version: 1.18.1/1.18.2
Mod Version: fabric0.43.1-1.10.2/fabric0.47.10-1.10.3
Fabric Version: 0.14.6
Fabric API Version: 0.45.0/0.53.4

You can still see the time left on the current effects when inside the inventory (top right). Either the timer needs to be hidden or the effect background should be rendered.