Update to 1.4.9. From the changelog:

API:

* Document::add_posting(): Fix bugs with the change in 1.4.8 to more
  efficiently handle insertion of a batch of extra positions in ascending
  order.  These could lead to missing positions and corrupted encoded
  positional data.

remote backend:

* Avoid hang if remote connection shutdown fails by not waiting for the
  connection to close in this situation.  Seems to fix occasional hangs seen on
  macOS.  Patch from Germ叩n M. Bravo.

(schmonz)