In the message box, when you start typing, LC treats the typed portion as filter criteria and will restrict what is presented in the "text entry" field to strings that start with the same text whenever you use the up/down arrow keys. For example, if you type "put" into the text entry line and then use up or down arrow keys, the msg box will cycle through all of your previous "put" commands.
In the past I would often go into the message box and just start scrolling through previous commands until I found the one I was looking for. This "filter" behaviour really helps to limit the search. Once you've found the previous command you are looking for, tap once on the right arrow key to complete the entry.
You're welcome
Mark