There are currently no open bugs.

"backbone" versions published in Ubuntu

Bionic (1.3.3~dfsg-3): universe/web
Artful (1.3.3~dfsg-2): universe/web
Zesty (1.3.3~dfsg-1): universe/web
Xenial (0.9.10-3): universe/web
Trusty (0.9.2-4): universe/web
Precise (0.5.3-2): universe/web