Package mode broken in REPL on Win11 unless started through VSCode extension

General Usage
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1

Ok, this is a weird one: if I start the Julia 1.12.6 REPL on my Windows 11 machine by opening up cmd.exe or PowerShell and typing julia in the prompt, it reads my startup.jl and duly starts the REPL. However, pressing ] to start package mode fails, even if enter using Pkg first. On the other hand, if I start the REPL using the keyboard shortcut for the Julia extension in VSCode (Alt-J, Alt-R), then package mode works fine. The executable path in the extension settings is empty, so I don’t think it’s using a different install or something.

Using where julia in cmd returns the following:

C:\Users\ducks\AppData\Local\Microsoft\WindowsApps\julia.exe
C:\Users\ducks\AppData\Local\Programs\julia-1.12.6\bin\julia.exe

However, manually starting both executables results in the same issue, so it shouldn’t depend on that distinction (I also don’t know why I have both). Here’s the result of versioninfo():

Julia Version 1.12.6
Commit 15346901f0 (2026-04-09 19:20 UTC)
Build Info:
  Official https://julialang.org release
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: 12 × AMD Ryzen 5 3600 6-Core Processor              
  WORD_SIZE: 64
  LLVM: libLLVM-18.1.7 (ORCJIT, znver2)
  GC: Built with stock GC
Threads: 1 default, 1 interactive, 1 GC (on 12 virtual cores)
Environment:
  JULIA_EDITOR = code
  JULIA_VSCODE_REPL = 1

The only difference between running this in extension-started REPL vs the manually-started REPL is the Environment block, which is missing in the manually-started REPL’s output.

Lastly, here’s my startup.jl. As a reminder, both methods of starting the REPL read this file.

atreplinit() do repl
    try 
        @eval using Revise, Infiltrator, OhMyREPL
        println("All packages loaded successfully")
    catch err
        println("Issues loading packages")
    end
end

This does remind me of one other weird distinction: when manually starting the REPL, it prints the error message, then the success message. When using the extension to start it, it prints the success message twice. I have no idea what’s going on, but maybe it’s connected. Any insight would be greatly appreciated!