### sparse version checks - [x] I checked that this issue has not been reported before [list of issues](https://github.com/pydata/sparse/issues). ### Describe the bug - https://sparse.pydata.org/, which is an alias for https://sparse.pydata.org/en/stable/, points to the documentation of 0.15.1, with the obsolete layout - https://sparse.pydata.org/en/0.15.5/ uses the obsolete layout - Both https://sparse.pydata.org/en/0.15.5/changelog.html and https://sparse.pydata.org/en/latest/changelog/ stop at 0.15.1