In the mIRC script editor, if it is still opened after entering the routine that "save" the code ({} button, changing tab, etc), the undo/redo options become unavalaible.
Even though mIRC disables the undo/redo options under the 'Edit' menu when this happens, the standard combinations ctrl+z or ctrl+y should still work but don't, which indicates that it is intentional.
I don't see any reason to prevent that feature in this case and I would like to see this changed.

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