Seems to be broken in 10.13

[dado3212]

Unless I'm doing something wrong, I think Apple implemented Library-Validation for SystemUIServer.

I'm getting Error loading /Library/Application Support/SIMBL/Plugins/BatteryExtra.bundle/Contents/MacOS/BatteryExtra: dlopen(/Library/Application Support/SIMBL/Plugins/BatteryExtra.bundle/Contents/MacOS/BatteryExtra, 0x0109): code signature in (/Library/Application Support/SIMBL/Plugins/BatteryExtra.bundle/Contents/MacOS/BatteryExtra) not valid for use in process: mapping process is a platform binary, but mapped file is not and Library Validation failed: Rejecting '/Library/Application Support/SIMBL/Plugins/BatteryExtra.bundle/Contents/MacOS/BatteryExtra' (Team ID: <id>, platform: no) for process 'SystemUIServer(58404)' (Team ID: none, platform: yes), reason: mapping process is a platform binary, but mapped file is not

[dbolger]

Don't know if you're still trying to solve this issue, but your AMFI is still enabled. Make sure it is disabled.