Upon trying to load a new server in the last few snapshots (19w11a,b) I have experienced the misloading of multiple datapacks, like Xisumavoid's tweaks to minecraft. I have searched for other issues related to this, but have yet to find one with actual report info. Here is my report information. The data packs that cause this issue are located at https://xisumavoid.com/vanillatweaks/
The log prints an error. That data pack is outdated and broken.