Steps to Reproduce
1. run the attached example
2. uncheck "Add Sheet" to disable ADD_SHEET, COPY, CLEAR
COPY and CLEAR buttons are still available
ADD_SHEET is disabled.
1. toolbar button of COPY and CLEAR are disabled
2. hotkey for COPY are disabled (ctrl+c)
1. if you call disableUserAction() in doAfterCompose(), it can disable functions, buttons on the toolbar are disabled.
2. COPY and CLEAR are just 2 examples, other functions might not work as expected, either.