AI Version: 25.2
OS: MacOS 11.2.1
Using CPU & GPU Preview

Problem:

• With an object selected, open the Properties Panel.
• Click in the Opacity field and use the keyboard to increment the opacity up or down.
• Note that the object's opacity doesn't change unless the change is accepted either by pressing the Return key, or clicking into the artwork.

Expected Behaviour:

• As the opacity is adjusted using the keyboard, the artwork should demonstrate the changed opacity.

Notes:
- If you use the Transparency Panel, and adjust the Opacity there, the keyboard commands are recognized as usual.