Hello,
I am wondering if it is possible to add the Boolean NOT to the custom filter.

For instance, I have may items tagged as "rental" for tasks that require a special rented tool. I would like to see tasks that do NOT require that tool. Because the advanced search is structured as "Tag IS /tagname/", my only choice currently is to tag all items as "rental" or "non-rental". However, this would significantly increase the work of entering a task. If the NOT function were available, I could label only a fraction of my tasks, and then search for IS "rental" or IS NOT "rental".

I think this would expand the functionality of the filter enormously, and be of relatively little cost in terms of programming.

Thanks for your consideration.
-D