Avoid Guzzle 6.5.0 (aka How to fix “Use of undefined constant INTL_IDNA_VARIANT_UTS46” on CentOS 6)

There’s a bug in Guzzle 6.5.0 in which it does not play nice with systems that have an older ICU library (which PHP’s Intl extension uses). CentOS 6 for example ships with a very old ICU version, without any (offical) means of updating it. The bug should be fixed in (the unreleased) Guzzle 6.5.1. It […]