hi @Freerk_Lap ,
I remember that @Paul_Danyliuk has solved this before, but I could not find it directly so below how I would handle it (but I guess that Paul had a different way).
- First we turn the canvas column into a JSON object
- second we count the checkboxes
- third we note how many of these are checked
- the last step is comparing step 2 & 3
the rest is obvious
cheers, Christiaan