UPDATE (EU):
The World of Tanks servers will be unavailable on 21.12.2017 from 05:00 – 05:45 CET due to this update.
On Thursday morning, December 21, a micropatch will be rolled out which will change the mod folders – new ones being: /res_mods/0.9.21.0.2 and /mods/0.9.21.0.2
The patch fixes some interface bugs and will seriously break the mods. GG WG.