Can't pick "Show value" valuemapid from dropdown in Item config?

[GeoffE]

We're running into a very odd problem. It seems that we're no longer able to pick a valuemapid in the Zabbix Item configuration screen.


(this is a default Zabbix Agent Ping check Item)

The "Show value" dropdown... doesn't drop down. And looking at the HTML source, it's not populated with any data, either.

This isn't breaking anything, but it's preventing us from being able to modify existing items - which is a problem. Several of our items show no value at all for the dropdown:


(this is one of our custom K8 monitoring items)

There's nothing in the field. Clicking on it does nothing, and there's nothing in the HTML source to pick from.

Attempting to update the Item fails, of course, with this error message:

• Field "valuemapid" is not integer.

We're using the latest (5.2.5) version of the Zabbix server. And there are still value maps defined; clicking on "Show value mappings" displays them all, as expected.

Any assistance in fixing this would be appreciated.

[GeoffE]

Also, if it helps any, here is the HTML log of the submission:

127.0.1.1:443 172.24.1.4 - - [02/Mar/2021:15:49:59 +0000] "POST /zabbix/disc_prototypes.php HTTP/1.1" 200 17863 "https://zabbix.example.com/zabbix/disc_prototypes.php?form=update&parent_discoveryid =2673699&itemid=3166490" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.190 Safari/537.36"
127.0.1.1:443 172.24.1.4 - - [02/Mar/2021:15:50:00 +0000] "GET /zabbix/jsLoader.php?ver=5.2.5&lang=en_GB&showGuiMessaging =1 HTTP/1.1" 304 217 "https://zabbix.example.com/zabbix/disc_prototypes.php" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.190 Safari/537.36"
127.0.1.1:443 172.24.1.4 - - [02/Mar/2021:15:50:00 +0000] "GET /zabbix/jsLoader.php?ver=5.2.5&lang=en_GB&files%5B0%5D=eff ects.js&files%5B1%5D=class.cviewswitcher.js&files% 5B2%5D=multilineinput.js&files%5B3%5D=multiselect. js&files%5B4%5D=items.js&files%5B5%5D=textareaflex ible.js&files%5B6%5D=class.tab-indicators.js&files%5B7%5D=servercheck.js HTTP/1.1" 304 217 "https://zabbix.example.com/zabbix/disc_prototypes.php" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.190 Safari/537.36"
127.0.1.1:443 172.24.1.4 - - [02/Mar/2021:15:50:00 +0000] "POST /zabbix/zabbix.php?action=notifications.get&sid=080fff9952 6d15fb&output=ajax HTTP/1.1" 200 2118 "https://zabbix.example.com/zabbix/disc_prototypes.php" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.190 Safari/537.36"

[GeoffE]

I was able to work around this by explicitly setting the value, via modifying the DOM (using Chrome's inspector) to insert an actual value (mapping to "As is").

<input name="valuemapid" type="hidden" value="0">

The original HTML was:

<input name="valuemapid" type="hidden" value>

This is obviously not ideal, but at least it let me make the necessary changes. I'm guessing this means that there's a bug in the PHP... should I submit this via the support site?