[BUG] Git Bash no longer detaches GUI processes with & in version 2.51.0

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What did you do before the bug happened? (Steps to reproduce your issue) I installed the version Git-2.51.0-64-bit.exe.

What did you expect to happen? (Expected behavior) I expected the same behavior as with Git-2.45.2-64-bit.exe. In that version, I could use Git Bash to run Makefile targets that launch GUI applications (like Vivado) using the command chaining or backgrounding operator (&). This allowed the GUI tool to open while the Git Bash console remained responsive. I could continue typing commands even with the GUI still running.

What happened instead? (Actual behavior) With version 2.51.0, this behavior no longer works. When a GUI tool is launched using &, the Git Bash console becomes blocked and does not accept further input until the GUI application is closed.

What's different between what you expected and what actually happened? Previously, using & to launch a GUI application would detach it from the shell, allowing the console to remain interactive. In Git 2.51.0, the shell remains blocked until the GUI process exits, which breaks workflows that rely on non-blocking GUI launches.

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[System Info] git version: git version 2.45.2.windows.1 cpu: x86_64 built from commit: 91d03cb2e4fbf6ad961ace739b8a646868cb154d sizeof-long: 4 sizeof-size_t: 8 shell-path: /bin/sh feature: fsmonitor--daemon uname: Windows 10.0 19045 compiler info: gnuc: 14.1 libc info: no libc information available $SHELL (typically, interactive shell): C:\Program Files\Git\usr\bin\bash.exe

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