Main editor is halfway down the screen and will not move back up.

Whenever Scrivener 3 is open in full screen the Main Editor is halfway down the screen. I have gone through the Preferences and tried to drag it back up but to no success. Would anyone be able to guide me on how to fix this please?

First thing, please use Scrivener > Check for Updates… to make sure you’re running the latest version of Scrivener, 3.1.5, as there have been several fixes for macOS Catalina compatibility including this sort of resize/drawing issue.

I’ve just tried to do that and it keeps coming up with “Scrivener can’t be updated when it’s running from a read-only volume like a disk image or an optical drive. Move Scrivener to Applications folder using Finder, relaunch it from there, and try again.” My Scrivener is already in the Applications folder (unless I have incorrectly identified where it is) so I’m not sure what to do.

I think I managed to fix it by downloading a later version from the website. Its just left me with two copies on the computer, Scrivener and Scrivener 2, but I can work with that. Though if there is a fix for the first one I’d be grateful to know it.

Try this: in Finder, click on the Go menu and then on Applications (alternatively, hit Shift-Command-A). This will open the Applications folder on your computer hard drive. Look for You can find out which is the new one and which is the old one by choosing the menu item File->Get Info. Make sure it is not running (you can cycle through applications that are running by hitting Command-Tab repeatedly) and drag it to the trash. If you find a file that has the extension .dmg, that should not be in your applications folder, That is a disk image. You ought not to run any application from a disk image. you need to open the disk image and move the program inside it to the applications folder. I’m guessing that this might be what has happened, but it is only a guess. It is also possible that the disk image is elsewhere on your computer, for example in the Downloads folder. In any case, the disk image is not needed when you have copied the program to the applications folder, so you can trash it.