Inspector causing severe fps drops in editor play mode

The actual “PlayerLoop” fps is fantastic, but the EditorLoop fps just tanks it to well below 60 fps. It’s near impossible to playtest properly in play mode in the editor when I have any object selected in the Inspector. I started noticing it around 2017.2 or 2018.1 but has gotten worse with each new editor version. I have no idea how to remedy it since it doesn’t appear to be anything related to what I’m doing, unless I’m doing something very wrong somewhere in a way that’s causing the inspector rendering to do things it’s not supposed to. But I use very few custom editors, and the slowdown happens with objects selected that don’t have a custom inspector as well. So I have no idea what to do.

Inspector doesn’t generate that much garbage when EditorLoop is being profiled out of play mode. It’s only in playmode that the absurd amount of garbage is generated from drawing the Inspector.

Could it be the editor trying to reserialize every value in the inspector potentially multiples times per play mode frame for some reason?

It just started happening to me, but only for one gameobject and I can’t pinpoint why. I have tried [hideininspector] any value that changes during runtime, but this does not help. Admittedly this gameobject script is very busy during gameplay, but the framrate is unaffected unless this gameobject containing the script has focus in inspector. Figure anything out?

I’m afraid not. I just got used to deselecting all gameobjects in playmode for playtesting.