Mouse drag scrolling being enabled and configured to the middle mouse button (Settings -> editor -> mouse drag scrolling -> Mouse Button To Use: Middle Mouse) appears to break right clicking on the main editing area on a piece of code. Turning off mouse drag scrolling appears to fix this. Restarting with it enabled does not enable right click to function again
It seems like the mouse drag scrolling plugin isn't actually enabled correctly initially, as disabling and reenabling the plugin does not allow any mouse dragging to occur, it only works (and then breaks right click) after turning mouse drag scrolling off and on again in the editor settings
I was able to copy across the version of dragscroll from v13650 (dated 23/10/23) and overwrite 13739's dragscroll plugin, and it fixed the problem, so there appears to be a problem in a newer version of dragscroll
If you need any other information for this, please let me know! v13650 is the last version of C::B I've used before updating so I don't know an exact nightly when this bug occurred