This attribute is only applicable to menu blocks, if the condition is
false, the menu block is not displayed to the user (the symbols
contained there can still be selected by other symbols, though). It is
- similar to a conditional "prompt" attribude for individual menu
+ similar to a conditional "prompt" attribute for individual menu
entries. Default value of "visible" is true.
- numerical ranges: "range" <symbol> <symbol> ["if" <expr>]