Python 3.14 webbrowser regression when launching vscode:// URI on macOS

Bug report

Bug description:

In Python 3.13.13 on macOS 26.3.1, I run __import__("webbrowser").open("vscode://"): it opens Microsoft VS Code
Same machine, in Python 3.14.2, same code: opens Chrome instead

I observe the same behaviour with Python 3.15.0a8

One line test case (using uv):

uv run --no-project --python=3.14 python3 -c '__import__("webbrowser").open("vscode://")'

In my actual use case, the URI is more complex, something like vscode://vscode-remote/ssh-remote+MYDEVBOX.example.com/workspaces/MYPROJECT.code-workspace – but vscode:// is enough to reproduce it

CPython versions tested on:

3.14

Operating systems tested on:

macOS

Linked PRs

• gh-155859

从 webbrowser.open() 入口点开始，在 macOS 上使用 Python 3.14 和提供的 uv 命令重现该问题。针对 vscode:// URI，将其行为与 Python 3.13 进行比较；当该 URI 启动 VS Code 而不是 Chrome 时，即表示完成。