1400.023 Error MainLoop.cpp:1510: Exception at tick 514: The mod Quality cursor (0.1.1) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event quality-cursor::qc-alternative-pipette (ID 218)
quality-cursor/control.lua:163: attempt to index field 'selected_prototype' (a nil value)
stack traceback:
quality-cursor/control.lua:163: in function <quality-cursor/control.lua:162>

Factorio version 2.0.55
Quality cursor 0.1.1

Thanks for the report, this has been fixed in 0.1.2