Code mode vs design mode

Both of these modes extend ActorScript or SceneScript which extend Script. 

for code mode:
code window snippet in design mode cannot be extended.

exclude unwanted imports to improve performance.

remove Design_XX_XX_ in internal names. 

for design mode 

Custom code can be inserted while snippets cannot be inserted to code mode. 

Each function is sectioned

Easy to scroll

Preview code which can be later used for other behaviors for in code mode. 

Definition or meaning

code window. This window cannot be extended. at least for Stencyl 4.0.4 and earlier version.