Unfortunately there is no such magic bullet for trawling through bug reports from users, but pushing more work out to the reporter can be reasonably effective at avoiding that kind of time wasting. Require that the reporters communicate responsively, that they test things promptly, that they provide reproducers and exact recipes for reproduction. Ask that they run git bisect / creduce / debug options / etc. Proactively close out bugs or mark them appropriately if reporters don't do the work.