It's very easy to delete the wrong block, the wrong extension, to move the entire block instead of a part,.... Why there is no UNDO function??
HEEEEELLLPPPP I don't want to re do my app ! I've deleted an extension but 2 has been deleted!
Deleting extensions requires an irreversible deletion of files from the App Inventor server. You are prompted when deleting an extension that it is destructive.
1 Like
Thinking it will delete selected unused extension, I've click on ok to delete. No idea why 2 extensions are deleted in the same time!
In this kind of application, an undo option is very mandatory because errors can affect very big changes!
Error is human ! Have you never move a block by error and don't remember exactly where it was placed???!
I have never encountered anything like this, where deleting one extension deletes another. I have done tests and it is not even possible to select two extensions because an error is displayed. So in my opinion it is not possible to delete two extensions at the same time, unless they are two extensions in one.
Besides, before any major changes, you should make a backup copy of the project, so that later in case of failure you can restore the previous state.
Undo function works for blocks but does not work for restoring deleted components.
1 Like
what extensions you deleted? if several extensions are in same package, delete one of them will delete all.
2 Likes
I must say I'm working on a tablet.
Very very easy to move, delete by mistake! Just by scrolling screen, blocks can move with.
When I keep touching a blovk, to can see menu like duplicate,... The bottom of this menu appears to much on top of screen and not possible to select anything 9 times on 10.
I keep what I've said : IT'S STUPID TO DON'T HAVE AN UNDO OPTION FOR THIS KIND OF PROGRAMMATION ! Try it on a phone or tablet !
One extension was about notifications listener phone and the other was background screen on. This last extension was not good for what I need. I've deleted all block about it and selected this extension to delete but two have been deleted in same time.
I know it's not possible then how it happened??? Not all extensions have been deleted, just 2. 
. I don't want to do my app again.
It was for my mother (93yo), to alert him when she receive specific notification. 
You probably learned a lesson: backup your project!
Taifun