Hi
Any news?

I could not reproduce it on a more simple scenario, where key point is ti use dependent item in trigger and {ITEM.LASTVALUE} macro in trigger name.

It's strange that for 2nd item in expression you do a comparison (>0) which should work for numeric items, while on history we see that the item collected Str/Text values.
It means that something is strange in your case.

Please try to reproduce the issue with more simple setup, with simple dependent item, without any preprocessing steps etc. Then step by step change it to be similar like in production to find out what exactly fails. I suppose this way you will find a misconfiguration on your side.
 

I need to use in the trigger the information from the second item, for this I added it to the expression. Since this is a text item, I use length(*last(/Template/item))> 0*.
Dependent items were originally created to use preprocessing, I am not using anything too specific here.
If the trigger expression uses dependent items, then the trigger must fire only after the data from all dependent items has been successfully saved to the database. In my case, the data from the first item has already been saved, the trigger fired, after the unknown number of milliseconds the data from the second item was written, and as a result we get an incorrect alert.
It is difficult to reproduce it, usually everything works fine.

First item:

json = JSON.parse(value);
if (json.length === 0) {
    return value;
} else {
    res = ""; 
    json.forEach(function (o) {
        res += JSON.stringify(o.BLOCKER)+":"+
            JSON.stringify(o.BLOCKED_OBJ)+":"+
            JSON.stringify(o.LOCK_TYPE)+"\n";
    });
    return res;
}

Second item:

json = JSON.parse(value);

function getValue(data) {
    res = "";
    data.forEach(function (o) {
        res += JSON.stringify(o.BLOCKER)+":"+
               JSON.stringify(o.BLOCKED_OBJ)+":"+
               JSON.stringify(o.LOCK_TYPE)+", ";
    });
    return res.slice(0, -2);
}
if (json.length > 3) {
    res = getValue(json.slice(0, 3));
    res += " + "+(json.length-3)+" more blockers";
} else {
    res = getValue(json);
}
return res;

Ok, I did not spot length() function, that's ok for 2nd part of expression.

Well, it's about trigger processing refactoring, which is not a bug.

If you have logical dependencies of  two items (disregarding that they are dependent on the same master) used in single expression, you should not use so sensitive function like last().
Order of items processing is not guaranteed, different history syncers may work on write cache,  so order of parts of expression evaluation is also not guaranteed.

I do not have other suggestions than close it as Won't fix.

I feel like it's duplicate of ZBXNEXT-6284.
Closing as duplicate.