cmd = 0 Push terminal title (or icon name) to an internal stack for later restore.
See pop terminal title for the corresponding pop operation.
If cmd = 0, cmd = 2 or the stack is empty saves the terminal title to the stack, otherwise duplicates the title of the top-most stack entry.
If cmd = 0, cmd = 1 or the stack is empty saves the terminal icon name to the stack, otherwise duplicates the icon title of the top-most stack entry.
See also set window title and icon name, change icon name and change window title for details of the titles.
🛈 xterm has no limit for the stack size.
🛈 The stack has a size limit of 8 items.
🛆 vte does not support the icon title and just ignores the sequence if cmd = 1.