I could reproduce.

Selecting multiple objects break custom trigger target values of some VRChat component in Unity editor. It will occur on VRC_MidiNoteIn, VRC_AudioBank and VRC_OscButtonIn.

(It doesn't occur on VRC_Station because multiple objects editing is not supported by its custom editor. VRC_DestructibleStandard has trigger definition, but that are different format.)

For dev:

This is problem of CustomTriggerTargetDrawer in VRC_TriggerEditor.cs

These pages would be helpful.

I think we need BeginProperty - BeginChangeCheck - EndChangeCheck - EndProperty pattern for each properly inside VRCSDK2.VRC_Trigger.CustomTriggerTarget