Some kinds of macros maintain a list of objects : Unmasking macros, Masking macros, Macro of animation with trace, of trace auto or macros of loops.
To remove objects from the macro after the creation of the macro, use tool at the bottom of the left toolbar and choose Remove objects from macro.
A dialog box pops up displaying available macros.
Click on the macro in the list and validate.
The objects of this macro are now blinking.
Click on the objects you want to be remove from the macro.
Click on the red button STOP to finish.