Merging happens on the fly and the compressing is scheduled. Done should only be trigged once CSS or JS has completely finished. We could add a new action for when merging has occurred. Would this be helpful?
Thanks for your feedback! I’m looking for a way to reliably purge page caches. Ideally an action for this should fire on any new files generated so old pages in cache don’t point to expired CSS and JS resources. Is a new action needed for this to work? CSS minification is enabled for my setup, JS is not.
A new version of MMR is ready to be released. I’m just waiting on approval of a few additional plugins. This new version will include a new action: merge_minify_refresh_merged. You should be able to use this to flush your HTML cache. I will mark this as resolved. If the new version of MMR doesn’t work as planned please open a new ticket.