[Vinifera Bug] When the game is in Frame Step Mode, if the window loses focus it locks up

[MNOrac]

Description

When the game is put into frame step mode it functions as expected unless the game window loses focus, at which point it locks up and cannot be interacted with again. I believe this is a result of the shift to the SDL renderer.

Required Code (optional)

No response

Steps To Reproduce

With the game in windowed mode, toggle frame step on. Click out of the window or focus another application, then back into the TS game window.

Expected Behaviour

The game should regain focus, it should be possible to navigate the viewport around the map, toggle frame step off or advance frames, and otherwise interact with the game.

Actual Behaviour

The window freezes.

Version

1cf887b

Additional Context

No response

Final Check

• I added a very descriptive title to this issue.
• I used the GitHub search to find a similar issue and didn't find it.
• I have attached as much information as possible (screenshots, debug and exception logs, etc).