For debugging the Python test suite on the Emscripten platform, it's quite useful to be able to inject a breakpoint for the JavaScript debugger in Python code. This is particularly helpful when debugging problems with the file system -- the code paths I want to inspect are hit hundreds of times on startup. Inserting a breakpoint directly above the failing Python code makes everything much easier.

Linked PRs

• gh-127627: Addposix._emscripten_debugger function #127628