How do I preview my final edit in Lightroom?

[FarFocus]

I remember a while ago while using lightroom you could select a shortcut on your keyboard to preview you final edited photo in lightroom. There were 3 options, with 3 variable settings to black out the background panels and controls so that only you image was visable. I thought it was "command + L" which you clicked up to 3 times to roll through the 3 black out options. I can't seem to find any reference to it on this new version of Lightroom. Does anyone else remember this preview option? 

[Jim Wilde · Accepted solution]

Does anyone else remember this preview option? 

By @FarFocus

That "lights out" option still exists in the other version of Lightroom, now known as Lightroom Classic (LrC). The version of Lightroom you are now using (known as Lightroom Desktop) is not a replacement for LrC, but is a rather different version which does not have all the features that LrC has, including the "lights out" mode. LrC is the up-to-date version of the Lightroom that you remember from a while ago, has all the original features but with a host of new and improved features.

The easiest option if you want to preview your image using your Lightrom Desktop app with the rest of the screen blacked out is to use the "F" key, which puts you into full screen mode with the black surround.

[FarFocus]

Thank you for your reply, I found it very helpful