Can this be added as an option in the editor? It’s very annoying having to deactivate tons of sub-events by hand!
I agree. Deactivating an event, should deactivate all of its sub events.
In fact, I think that sub-events are disabled when the event is disabled but it’s not shown in the editor.
lol
The time knowing this would have saved me…
Can we please show this in the editor?!
Agreed, the editor should communicate that to the end user.
While we’re at disabling things, could we add option to disable specific actions/conditions of the event instead of the whole event? When debugging my games I’ve often longed for such option where you know which event causes troubles, but can’t pinpoint which condition/action exactly is wrong.
You can quickly do that by deleting that line, running the code, and then ctrl+z to undo. For multiple lines of event, just ctrl+x them out and then undo. Unless there is a shortcut key made for deactivating part of an event, then it will be slower than doing it by this method!
And what if you need to save & turn off computer AFTER deleting line because you got important call (say your sister is in hospital)? Gone Forever! Happened to me more times than I’d want to (gone actions/conditions, not sister in hospital as I obviously have no sister). And then, especially if action/condition in question had some complicated formula in it, try to recover it from memory.
I can’t imagine a situation in which you have time to hit ctrl + s to save the game but don’t have the time to hit ctrl + z before doing so.
Really. 
Also, before I make ANY major change in a game (e.g. testing out a major formula) I always make a save file, just in case. Mostly because… What if you run the game and it crashes due to the change you just made?!
Out of topic:
Haha, I save a new version of my projects EVERY time I made (even a minor) change.
The current project I’m working has reached 78 different versions of itself.
I know that seems very obsesive but I do it for some reasons:
- That delivers me from going through some debugging hells
- I can easily retrieve versions of previously used algorithms
- Reviewing the sequential progress trough the different versions of my projects allows me to learn about my creative process and how to organize and optimize it to develop future projects in less time and more efficiently
Git could probably work with GDevelop project and is probably a more convenient method. 
When you deactivate an event line, it’s subevent lines should also get greyed out - to communicate to the user that they also are disabled!
I think that this is for a bug report!