Backported the code of four hookscripts from 4.x.

* FINDTARGET, BARTERPRICE, WITHINPERCEPTION, and INVENTORYMOVE. For
unifying the behavior of common hooks between 3.8 and 4.x.

Added the example script of WITHINPERCEPTION from 4.x.
Updated gl_highlighting_lite.

artifacts/example_mods/ItemHighlight_Lite/gl_highlighting_lite.ssl

@@ -100,6 +100,11 @@ procedure KeyPressHandler begin
    end
 end
 
+procedure InventoryMoveHandler begin
+   // remove item outline when player picks up the item
+   if (isHighlight and get_sfall_arg == 7) then set_outline(get_sfall_arg, 0);
+end
+
 procedure start begin
    if game_loaded and (sfall_ver_major < 4) then begin
       call InitConfigs;
@@ -116,5 +121,6 @@ procedure start begin
       highlightFailMsg2 := Translate("HighlightFail2", "Your motion sensor is out of charge.");
 
       register_hook_proc(HOOK_KEYPRESS, KeyPressHandler);
+      register_hook_proc(HOOK_INVENTORYMOVE, InventoryMoveHandler);
    end
 end

artifacts/example_mods/ItemHighlight_Lite/readme.txt

@@ -17,5 +17,5 @@ Also, you should disable the built-in function in ddraw.ini (ToggleItemHighlight
 
 Note that due to the lack of newer game hooks in sfall 3.8.x, there are some minor visual glitches with the lite version:
 - items will be kept highlighted when entering combat while holding the highlight key.
-- when you pick up items while holding the highlight key, they will be kept highlighted if you drop them on the ground.
+- when you pick up items while holding the highlight key, they will be kept highlighted if you drop them on the ground (fixed for 3.8.18+).
 Both glitches can bo solved by pressing and releasing the highlight key again.