@Hansaplast Thanks, there is no setCollectionBehavior property in the NSWindow in my environment, I'm using fpc 3.2.0.
@madref I've tried it, the Full Screen button is still there.
@trev I agree with you, my application's UI flow probably doesn't fit Apple design principle, so when the form enters full screen it is not user-friendly.
I have several forms in my application:
Main Form
Editor Form A, B, C ...
The Main Form shows data list, user can open Editor Form to edit data, and they would open multiple Editor Form to do cross check. If the form enters full screen mode, switching between forms becomes difficult to use, that is why I want to replace Full Screen Button with Maximized Button.
I found an alternative way:
If form's PopupParent is set, the border icon will be Zoom (Maximized) not Full Screen.
I set Editor Form's PopupParent to Main Form on form activate, remove PopupParent on form deactivate to prevent Editor Form blocks Main Form.