I’ve been using LibrePCB for a while now, and have run into a problem with a component I need to place.
This is an SMT SPST switch with three electrical terminals and four mounting tabs which should go to ground. I had this part working and placed, but needed to clean up the PCB footprint.
Somehow, I broke something in the library. I’m including a screen shot of the error message that might help diagnose the issue.
Are you sure you edited the footprint? The error looks more like you edited the symbol or maybe the component. This should be fixable by removing and re-adding the symbol gate in the component: