and finally, the modules folder. Now I can publish and take a break

code/modules/fields/gravity.dm

@@ -0,0 +1,17 @@
+/datum/proximity_monitor/advanced/gravity
+	name = "modified gravity zone"
+	setup_field_turfs = TRUE
+	var/gravity_value = 0
+	var/list/grav_components = list()
+	field_shape = FIELD_SHAPE_RADIUS_SQUARE
+
+/datum/proximity_monitor/advanced/gravity/setup_field_turf(turf/T)
+	. = ..()
+	grav_components[T] = T.AddComponent(/datum/component/forced_gravity,gravity_value)
+
+/datum/proximity_monitor/advanced/gravity/cleanup_field_turf(turf/T)
+	. = ..()
+	var/datum/component/forced_gravity/G = grav_components[T]
+	grav_components -= T
+	if(G)
+		qdel(G)

code/modules/fields/turf_objects.dm

@@ -6,7 +6,7 @@
 	icon_state = null
 	alpha = 0
 	invisibility = INVISIBILITY_ABSTRACT
-	flags_1 = ABSTRACT_1|ON_BORDER_1
+	flags_1 = ON_BORDER_1
 	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
 	var/datum/proximity_monitor/advanced/parent = null