When there are two text elements superposed on the timeline and at the same place in the frame, and that one of them is disabled, it's often (always?) this disabled one which will be selected when I click on the program monitor to modify the enabled/visible text. By clicking, I end up modifying an invisible (disabled) text, without being able to select the enabled/visible one.
The only way to select the right one in order to modify it is then to remove the disabled clip from this place of the timeline...
I think it would be much more logical if it was impossible to select, on the program monitor, an element which is disabled in the timeline and therefore invisible in the program monitor (or at least if it was not prioritary on enabled/visible elements).