'Record not found' error saving Incident record - Contextual Search/Table Configuration

Hi folks,

I'm hoping someone has encountered this issue before.

I'm trying to 'Enable related search box' option on the Incident record in All > Contextual Search > Table Configuration, but I get an error (Record not found) when I hit Save. In fact, the error comes up when trying to save any type of change to the record. I've tested on all non-prod instances and the behaviour is the same across the platform.

I've twisted myself in knots trying to figure out what's going on here but can't seem to crack it. Any suggestions would be highly appreciated.

Thank you,

Zoran