Refactor #3878 #3922 #3963 #3983: Make temporary proto variable deletable
Merge commit 'a5c0c96331956787abe1bd4821260e21d070349f' into develop-3.0

* commit 'a5c0c96331956787abe1bd4821260e21d070349f':
  Refactor #3878 #3922 #3963 #3983: Make temporary proto variable deletable