Is there a way to use more than 1 monitor? Like be able to put the star chart, com screen or what ever on the second screen.
Elite can only utilize a single screen. (NVidia surround/AMD Eyefinity is to Elite a single screen that spans multiple physical screens)
There is no ingame options to open/use secondary screens.
It has been suggested to have Elite natively support more screens. I do like these kind of suggestions, but they also create another interesting controller nightmare, for example, lets say you could bring up the galaxy-map on a secondary monitor. and you are now on that monitor plotting a route, and you now see on the main monitor that something is about to go horribly wrong, yeah, you would have to leave the Galaxy map to be able to control your ship again.... So these kind of suggestions are not all that straight forward.
Other suggestions that have been made, is to be able to utilize screens/laptops/tables/phones/etc as auxiliary displays, to show different panels etc. The nice thing about tablets/phones are that they have integrated touch functionality, so no extra "controls" needs to be added. if using secondary screen then you would still need to "tab" over there and then we have the same issue as the above.
So there are multitude of possible ways FDev could enhance support to use more than one screen, all with their own good and bad points.
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If you have second screen you should already be familiar on running Elite in Borderless Window mode, so that it does not minimize every time you tab out of the game. And on the second screen you can open the favourite web-sites/tools that are useful for gameplay, but they are mostly limited to reading the log-file.