Its color bar flashes several signals:
If one timeframe is in a buy mode and the other in a sell mode, the signal is "No Trade Allowed", a red bar.
If both are neutral, then any trades are allowed, showing a blue bar.
When one is while the other is either or neutral, there is a green bar, allowing traders to buy and prohibiting shorting.
When one is while the other is either or neutral, a red bar signals that shorts are permitted, while long trades are not allowed.
Please check Dr Elders books available on amazon they are a great buy and a nice to read.
If the color is red there is no long trade, if the color is green there is no short trade (even tho in the crypto world you cant really open short position unless in some pairs who allow margin trading), and if is blue you can go both ways, so the scenarios are 3.