Spamming chat messages causes extreme lag and crashes servers.

I've reported this before, but it is still apparent in the newest Minecraft bedrock version, it is a very bad exploit. Basically people spam characters into the chat, and end up causing lag, or even end up crashing servers and realms. They either use small text or big text fonts, or the Mojang button symbols/stickers (the control buttons that you can copy and paste, or the food symbols) aka these  . A solution to this problem would be limiting the amount of characters a player can type into the chat, add a chat cool-down function or command for chats, also making it so players cannot use these symbols in the chat. I have attached a file of what it looks like in the chat when somebody spams it with said symbols .