BuildCraft version: 7.99.21
Forge version: 14.23.5.2796
Link to crash report or log: https://pastebin.com/9KUn56Jj
Singleplayer or multiplayer: multiplayer
Steps to reproduce:
1.Install Buildcraft and extrautils2-1.12-1.9.8 to forge server
2.Start the server for a while
3.Error appear
Additional information: None

Try setting advanced tooltips to false, either in-game (F3+H) or in options.txt

@InThayne This isn't related - as this crashed while looking at extrautils block properties, rather than getting item tooltips.