I don't think they are going to be many folks using this.

IIUC it was mostly and experiment from the early days of emscripten to try to get synchronous applications running in a worker. However, since it always takes over the whole browser window I can't imagine many folks actually using it.

The process for deprecating and removing features from emscripten is laid out out in https://github.com/emscripten-core/emscripten/blob/main/docs/process.md#deprecating-settings-and-features).

At any point in the process we may decide to delay or abort the deprecation and close this issue.

Deprecation checklist:

• Open issue (Can we deprecate --proxy-to-worker / -sPROXY_TO_WORKER? #25440)
• Perform global search for usage in public repos
• Send message to emscripten-discuss (https://groups.google.com/g/emscripten-discuss/c/oFCpwLbDLvU)
• Add "deprecation" warning to emcc (Mark PROXY_TO_WORKER as "under consideration for removal" #25442)
• Wait at least 4 releases or 2 months
• Remove feature