ID:2040346
 
(See the best response by FKI.)
Code:
#define MASTER_PLANE 0
#define DARK_PLANE -10
#define GUI_PLANE 10

/obj/master_plane
blend_mode = BLEND_MULTIPLY
appearance_flags = NO_CLIENT_COLOR | PLANE_MASTER
color = list(null,null,null,"#0000","#000f") // Completely black.
mouse_opacity = 0
plane = MASTER_PLANE
screen_loc = "CENTER,CENTER"

/obj/dark_plane
blend_mode = BLEND_ADD
mouse_opacity = 0
plane = DARK_PLANE // Just below the master plane.
icon = 'icons/planar_lighting/over_dark.dmi'
alpha = 30
screen_loc = "CENTER,CENTER"

/obj/dark_plane/New()
..()
var/matrix/M = matrix()
M.Scale(world.view*2.2)
transform = M

/mob
var/obj/master_plane/master_plane
var/obj/dark_plane/dark_plane

/mob/Login()
..()
master_plane = new
dark_plane = new
if(client)
client.screen += master_plane
client.screen += dark_plane


Problem description:

Hello! I am not sure if this is a bug or not, so I thought posting here first would be wise.

I have a simple two-layer lighting system set up that worked fine previously, when using /image rather than /obj, other than some very annoying bugs (such as the entire view rotating 90 degrees or scaling when the mob was rotated or scaled). I switched it to /obj as above to solve the bugs, which worked, but now it is impossible to right-click or left-click on anything below the lighting objs.

Setting the objs to be invisible, or removing them from client.screen, removes the issue entirely, so I would hazard that it relates to mouse_opacity in some way.
Best response
This could be related to this issue.
That does look very similar. Alright, cool, thank you. I'll wait and see what happens when the next set of fixes are released.