Sometimes on Windows, JetBrains Rider will launch off screen. Alt Tabbing will not bring it back into view. It seems this a long standing bug with JetBrains products, but no resolution forthcoming.
Here's how to fix it.
- Alt-Tab the right window to the foreground
- Alt-Space to bring up the system menu for the active window (you won't be able to see this)
- Down arrow once to select 'Move' (again, it's out of view)
- Enter to select the menu item
- Down arrow to start the window move
- Mouse movement then will 'spring' the window into view.