[2026.3.0] UDSelect $EventData serialized

Hello,

Thank you for the report.

You are right about the cause.

In 2026.3.0, $EventData reaches your event handlers as a raw JSON string instead of a deserialized object.

This is a regression on our side, and a fix is in progress (ticket PSU-1353, for internal reference only).

It is targeted for 2026.3.2, which has not shipped yet.

You have two options in the meantime.

You can roll back to 2026.2.4, the last build without this problem.

Or you can stay on 2026.3 and convert the value yourself:


$value = if ($EventData -is [string] -and $EventData.Trim() -match '^(\{[\s\S]*\}|\[[\s\S]*\]|"[\s\S]*")$') {
$EventData | ConvertFrom-Json -AsHashtable
} else { $EventData }
This only converts values that look like JSON, so it stays safe after the fix.

Please also note that an empty text box now returns two quote characters.

A check such as if ($EventData) will return true even when the field is empty.

Documentation on app event data:
https://docs.devolutions.net/powershell-universal/apps/interaction

We will let you know as soon as the new build is available.

Best regards,

I notice this issue as well in 2026.3.1.
Already tested a workaround similar to this $value = if ($EventData -is [string] -and $EventData.Trim() -match '^(\{[\s\S]*\}|\[[\s\S]*\]|"[\s\S]*")$') {
$EventData | ConvertFrom-Json -AsHashtable
} else { $EventData }

and it works.
What I am not sure is, does this only happen in $EventData of UDSelect or $EventData in general?

Hello,

Thank you for confirming this on 2026.3.1, and for testing the workaround.

To answer your question, the problem is not limited to New-UDSelect.

The bug is in the shared code that passes event data to app event handlers, so $EventData can be affected in other components too.

We have also had a report of the same behavior with New-UDTextbox -OnValidate.

You can use the same workaround anywhere your app reads $EventData.

I also need to correct my earlier message: the fix is now targeted for 2026.3.3, not 2026.3.2.

That build has not shipped yet.

We will post here as soon as it is available.

Documentation on app event data:
https://docs.devolutions.net/powershell-universal/apps/interaction

Best regards,