[BUG] Set-PnPApplicationCustomizer fails to update ClientSideComponentProperties

[YuriySamorodov]

Reporting an Issue or Missing Feature

I'm reporting an issue with the Set-PnPApplicationCustomizer cmdlet not properly updating ClientSideComponentProperties.

Expected behavior

When executing Set-PnPApplicationCustomizer with updated ClientSideComponentProperties, I expect the customizer's properties to be permanently updated with the new tracking ID value.

Actual behavior

After running Set-PnPApplicationCustomizer to change the trackingID property, a subsequent Get-PnPApplicationCustomizer shows that the property value was not updated - it still shows the original value. Even setting the ClientSideComponentProperties to $null does not make any difference.

Steps to reproduce behavior

# 1. Connect to SharePoint site
Connect-PnPOlnine https://contoso.sharepoint.com/sites/Marketing

# 2. Check current application customizer properties
$customizerId = "a3cf2fa-6f14-44f0-892e-add9d7a3d561"
Get-PnPApplicationCustomizer -Identity $customizerId | fl *

# 3. Attempt to update the trackingID property
Set-PnPApplicationCustomizer -Identity $customizerId -ClientSideComponentProperties '{"trackingID":"GTM-SAMPLE1"}'

# 4. Verify the update (shows original "G-SAMPLE123" value instead of "GTM-SAMPLE1")
Get-PnPApplicationCustomizer -Identity $customizerId | fl *

# 5. Setting to null works, but removes all properties
Set-PnPApplicationCustomizer -Identity $customizerId -ClientSideComponentProperties $null
Get-PnPApplicationCustomizer -Identity $customizerId | fl *

What is the version of the Cmdlet module you are running?

PnP.PowerShell version 2.99.145 (nightly)

Which operating system/environment are you running PnP PowerShell on?

• Windows
• Linux
• MacOS
• Azure Cloud Shell
• Azure Functions
• Other : please specify

[KoenZomers]

Looks like you're providing the clientSideComponentId as the -Identity. It should be the -Id instead (c84b9595-...). Can you try it with that instead and add -Verbose? This will reveal if it found a customaction to update or not.