It just came to my attention that the custom criteria dropdown for Conditional Formatting has a "contains" option, but not a "does not contain" option. Also, the "Apply to format when condition is NOT met" button [which would solve this problem] only exists on the "select from a list" menu and not from the "define custom criteria" one.
In my specific case, we have a certain syntactic element [a double colon "::"] that we use to denote a list of certain values in a certain cell. I want to highlight that cell if it does not contain that "::". Cells that do not have that "::" may not be blank and aren't any specific string, so "is not blank", "is not equal to", and selecting options from the list do not work. "Does not contain" is the correct function. We can work around this with a helper column that does that check, but we're trying to keep clutter to a minimum, so I'd ideally like to avoid adding another helper column to every sheet we want to do this kind of formatting.
This feels like a really basic component that's missing. Either adding a "does not contain" logic option to the existing list OR adding the "Apply to format when condition is NOT met" button to the custom criteria menu would solve this issue.
In the meantime, does anybody have any idea why this functionality is missing? This seems like a really basic add that should have been there from the beginning.
