Message draft persistence

[naqerl]

Currently message draft got cleaned up on navigation or starting replying to another message. It'll be great if text will be persisted per chat room. This will save future users from "Oh, my message got deleted, i need to copy it before other actions"

As a possible solution I see using SessionStorage (to keep things light and to not care about cleaning it up manually) to save message text with key "campfire:draft:roomId" with some debounce. As an alternative, LocalStorage may be used for the case, if closing tab to cleanup draft would not be considered as a feature