Here's basic steps in order to fix this issue:

1. Press the right-click on the game and go into 'Properties' section
   
2. Click the 'Set Launch Options' button
   
3. Type in the following arguments into the text field:

Where '1920' is a horizontal resolution of one of your screens.

For three and more screen setups, there's a possible workaround by summing resolutions of two of your screens. Different setups will require different resolution summations.

For example, if you have three 1920x1080 screens if you sum two of them and put the result into WinX
string (1920*2-->3840, WinX=3840) it should detect your primary screen automaticaly each launch.

This should force the game to launch on your Primary Screen every time you launch the game.

I hope this guide will help you, it will stay relevant until the devs patch this issue.

Shoutout to Skinni for also finding this solution.

Shoutout to Kroporo for mentioning the summation of horizontal resolutions.