I'm using some code on Cadabra 1.x (still haven't ported it) and I found a bug in the newest version of 1.x
x a + x b; @factor_out!(%){x};
The output reads
1:= x a + x b; 1:= ;
This seems to be a bug in Cadabra 1.46. It works fine on Cadabra 1.42.
Thanks for letting me know. If there's any chance of moving to 2.x, that would be preferred, as it works there. If it's mission critical to have this work on 1.x, let me know by email and I'll try to sort something out.