I've never tried grepcode before it's gone (not a Java guy), but what I miss most is precise reverse search, i.e. "find all reference", instead of "go to definition". For example, try Chromium code search:

https://source.chromium.org/chromium/chromium/src/+/main:v8/...

Click on the "ToBoolean" function, it brings up all call sites across all Chromium projects.