OnSecondInstanceLaunch not being triggered when "Launch Program" is added to finish page of NSIS installer

[FunOrange]

Description

I've added a "Launch Program" checkbox to the last step of my NSIS installer. After the app is launched, nothing happens when the custom uri scheme is invoked from a normal, non-elevated process. I've outlined what the source of this issue is below.

To Reproduce

1. Modify wails.json to register custom protocol scheme as defined in docs (https://wails.io/docs/guides/custom-protocol-schemes/)
2. Modify build\windows\installer\project.nsi to include the following:

!insertmacro MUI_PAGE_WELCOME # Welcome to the installer page.
# !insertmacro MUI_PAGE_LICENSE "resources\eula.txt" # Adds a EULA page to the installer
!insertmacro MUI_PAGE_DIRECTORY # In which folder install page.
!insertmacro MUI_PAGE_INSTFILES # Installing page.
!define MUI_FINISHPAGE_RUN "$INSTDIR\${PRODUCT_EXECUTABLE}"
!define MUI_FINISHPAGE_RUN_TEXT "Launch ${INFO_PRODUCTNAME}"
!insertmacro MUI_PAGE_FINISH # Finished installation page.

3. Run wails build -nsis
4. Run the installer
5. Tick "Launch [program name]" checkbox
6. Observe that app runs in Elevated mode
7. open [urischeme]:// from a non-elevated process
8. Observe that second app window is not created, however OnSecondInstanceLaunch is not being called in the original elevated process.

Expected behaviour

Non-elevated second process should be able to do IPC with elevated first process in order to trigger OnSecondInstanceLaunch.

Screenshots

No response

Attempted Fixes

No response

System Details

# Wails
Version | v2.11.0


# System
┌───────────────────────────────────────────────────────────────────────────────────┐
| OS           | Windows 10 Pro                                                     |
| Version      | 2009 (Build: 26200)                                                |
| ID           | 25H2                                                               |
| Branding     | Windows 11 Pro                                                     |
| Go Version   | go1.25.5                                                           |
| Platform     | windows                                                            |
| Architecture | amd64                                                              |
| CPU          | 11th Gen Intel(R) Core(TM) i7-11800H @ 2.30GHz                     |
| GPU 1        | Meta Virtual Monitor (Meta Inc.) - Driver: 17.12.55.198            |
| GPU 2        | NVIDIA GeForce RTX 3070 Laptop GPU (NVIDIA) - Driver: 32.0.15.9174 |
| Memory       | 64GB                                                               |
└───────────────────────────────────────────────────────────────────────────────────┘

# Dependencies
┌───────────────────────────────────────────────────────┐
| Dependency | Package Name | Status    | Version       |
| WebView2   | N/A          | Installed | 144.0.3719.93 |
| Nodejs     | N/A          | Installed | 22.14.0       |
| npm        | N/A          | Installed | 10.9.2        |
| *upx       | N/A          | Installed | upx 5.1.0     |
| *nsis      | N/A          | Installed | v3.11         |
|                                                       |
└─────────────── * - Optional Dependency ───────────────┘

# Diagnosis
 SUCCESS  Your system is ready for Wails development!

Additional context

No response

[github-actions]

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