About another bug reported with a demo, with a search constraint “is empty / is not empty” which did not work, here the answer I get two weeks ago :
I just gave this a try on our test Airtable account and was able to filter successfully using is & is not empty. But, I had to make sure that my settings were set up correctly and it didn’t work if the field I was trying to reference was a linked field. Instead, I had to set up a lookup field that pulled in the data I cared about from the other table and build my constraint on that field. The other thing you could try would be to build a view on Airtable’s side with the particular filtering you want and then reference the view’s records. It will essentially accomplish the same thing but Airtable will be handling the filtering for you. Might be worth looking into.
Here a new demo (I’m gonna send another bug report)
Not any error shows up in the editor. This is just a text (see airtable API doc) :