Fan Settings and/or custom g-code by object

[kizzelwhix]

I'm running some test iterations with by-object printing to tweak bridging parameters for PETG. I've run into an issue, where I'd like to change my fan speed for bridges for each object - but finding no way to do that. So, I figured I could just go and set it manually via gCode at that layer - which apparently I cannot do. When I right click on the slider to add my gcode at that layer, it's greyed out, along with the add pause feature. Does anyone have a suggestion?