Noticed while working on T352308.
Currently mw.rcfilters is a public stable API by the definition expressed in https://www.mediawiki.org/wiki/Stable_interface_policy/Frontend however it is never used (https://codesearch.wmcloud.org/search/?q=mw%5C.rcfilters%5C.&files=&excludeFiles=&repos=) and appears in our JavaScript documentation.
Decision
- No longer populate mw.rcfilters. Instead use module.exports and mark the export as for internal usage.