Can I prevent players from launching the game?

Hi all, I have a very specific question. Is there a way to prevent players from launching the game in downtime? I have a splash page for them and a load up page, I'm asking specifically because my players tend to join often to look over notes and handouts. I want to be able to close the game so I can safely test rollable table macros, make sure NPC rolls are correct and other private information that uses the chat so I can clear it after with no chance of them seeing it. Is this possible? 

There is a chat command, /talktomyself, that limits the output to just you. I think that should handle 90+% of what you're concerned about.  I make sure to put the "Players" ribbon on a safe page before leaving the session, just in case, especially if the session ends in the middle of an encounter. 

That command would absolutely fix it!  Is this a thingI can toggle such that I type it once and then all things sent to chat are private until I toggle it off?

That is correct.  Once talktomyself  is on it is on until you turn it off.

It';s handy to create a macro containing the /talktomyself text, so you can just click it once to switch on and off.

note, /talktomyself eats up calls to API scripts. so you can't be in the mode if you want to test out APIs. EDIT: just noticed OP is Plus user so this would not apply.  but, i'll keep the comment up for general info.

That was my first reaction too, then I noticed Corbin is plus. But it's good to mention it for general info.

You can also make a copy of your game and test things in the copy.

Copy the page, it copies the players with ?

It can.  You have an option for what all is copied.

Niku said: Copy the page, it copies the players with ? Not copying a page, copying the entire game. See "Copy Game" in the Settings section of the Wiki: <a href="https://wiki.roll20.net/Game_Management#Settings" rel="nofollow">https://wiki.roll20.net/Game_Management#Settings</a>