Proposals can be modify even though they've received support or have been commented

Proposals can be modified even though they've been supported or commented, which can lead to unwanted situations. Let's say you can modify your proposal during 10 minutes, and you add at the last minute another idea to your proposal. Someone might have already voted for it and he might not agree with what you've added. He has no way tho (aka no notification) to know that you've modified your proposal. Maybe it would be better if, just like proposals that cannot be withdrown if they've been commented or supported, you cannot modify your proposal if someone has commented it or supported it? Or you receive a notification if a proposal that you've commented/supported has been modified.