Currently building on Heroku fails with a package error for libidn11. Since Mastodon uses idn-ruby 0.1.2 we should upgrade to libidn12
@@ -1,8 +1,8 @@
ffmpeg
libicu[0-9][0-9]
libicu-dev
-libidn11
-libidn11-dev
+libidn12
+libidn-dev
libpq-dev
libxdamage1
libxfixes3