When typing 3 blank messages in chat, Roblox shows a message that the chat filter is currently experiencing issues, but this should not be shown since this is not the case.
I believe this is due to the filtering device trying to filter a blank string. This could be solved by removing spaces before the first character and after the last character.
Steps to reproduce:
Open a place which supports roblox’s default chat
Type a space ( ) and press enter. Do this at least 3 times
A message in chat will appear saying the chat filter is currently experiencing issues.
I made a bug report in 2017 about the filter failing if the string is blank or is just spaces.
I marked it as fixed on my spreadsheet, but it looks like I incorrectly marked it as fixed because it is still a bug. For some reason, a HTTP 400 error is returned for strings that only have spaces.