As of now we are switching to using a custom SAHI build for CWB.  The first version is based on SAHI OS 5 and adds some customizations.  It's advised that all projects switch to the new build as soon as possible.
We created a custom open source build of SAHI for CWB.  This is the build we will use and maintain in the future.  

Whereas most CWB projects were using SAHI OS 4.4 until now, the new build incorporates all changes from SAHI 5 along with some customization (eg. placeholder attribute support for input types).  It is advised to upgrade to SAHI 5.0 as soon as possible.

Note that this build is specifically tailored to CWB and some of the default SAHI features that CWB does not use might be removed in the future.

Installation/upgrade instructions

Currently we only prepared a build for Windows 64 bit, if you need to make it work for another OS and can't figure it out by yourself, contact me or give a callout in the comments.

SAHI 5.0 should be running correctly at this point.  To ensure that your CWB projects use the new SAHI at all times, you must configure the path to SAHI in the CWB properties:

If you are running automated builds, you have to upgrade SAHI on every build server and ensure that the CWB properties on every server contain the right locations.