I have times ne question: I have when running seen after the introduction round the “Green flag” was indicated am as go that???

looks like some mod. A while ago, in S1 even iirc, there were some funny guys who made huge text all over he screen, using those big letters...
Only the server admin can do this, though. Spamming in the chat is another story.

An admin can make these texts appear on the screen, by starting a message with "/rcm_all". and "/rcc_all" to remove it.