@John1 made some improvements to REQUEST here:
As part of this work, REQUEST became more powerful, and also more of a special case in terms of security. So it is now enabled separately to experimental plugins with:
GRIST_ENABLE_REQUEST_FUNCTION=1
Please do review the description of this flag in the grist-core README before enabling:
enables the REQUEST function. This function performs HTTP requests in a similar way to requests.request. This function presents a significant security risk, since it can let users call internal endpoints when Grist is available publicly. This function can also cause performance issues. Unset by default.