With 3.8 there is a (currently undocumented) feature to stretch or shrink the in-game window to appear different from the display resolution.

• Open the registry editor (Win+R -> regedit.exe)
• Navigate to HKEY_CURRENT_USER\SOFTWARE\Team17SoftwareLTD\WormsArmageddon\Options (paste into the address bar if using Windows 10)
• Create two REG_DWORD values named WindowXSize and WindowYSize.
• Edit these values in mode to the size values you want* (e.g. 3840x2160). A common use would be to stretch to the desktop res borderless, so you can specify your desktop resolution.
• Check and/or edit DisplayXSize and DisplayYSize, this is the actual internal resolution and the one you see in game options. This resolution will be stretched or shrunk to the Window size you specified earlier. Shrinking a higher-resolution to a window of smaller size is actually new and was not possible in D3D9Wnd. So, for example, you can set a 1920x1080 game to run downscaled in a smaller window with borders.

In the future both of these should become more accessible in the game interface.

Note that this does not apply to the menus and for that SuperFrontendHD is currently required.

Another thing to mention is that super-resolution is already supported and you do not need to explicitly specify WindowX/YSize for it. So, if you set the game or video export to something higher than your desktop res, it will automatically be shrunk to fit the desktop. The aspect ratio will be preserved, unlike in D3D9Wnd.

IMPORTANT NOTE: This DOES NOT WORK with OpenGL renderers. They do not support scaling/stretching of any kind. You need to use a Direct3D 9 renderer for this. (DDraw works but is not visually good in my experience)

* Size of the window's client area, excluding the border.

In windowed mode, losing focuses drops the background music (from mounted CD image files) but can hear the other sfx. Odd one.

This is by design, however I think it would make sense to have multiple levels of "Play Audio in background" in future updates. So you could make it include music streams and work even when minimized. With the default being the current option's ON state.

Someone said that the update would include time-stamps in direct chat XD!

It can be done using reg tweaks or a custom format through registry.

Well the franchise has already been bigger than the "standard" 2D and 3D games, don't forget about Pinball, Blast, and Golf, technically you could consider this a spinoff just like those other games.
But the problem is that they are promoting it as a direct continuation of the series (hence the "Worms 2020" codename).

inb4 oldschoolers boycot 3.8 because the rope doesn't feel the same anymore

That would actually be surprising because the new rendering also decreases input lag.

To judge something from the changelog (which is quite outdated now and missing several things) is one thing, but to try it is something very different.
Even if you don't take into account all the extended scheme options, you will still want to launch the game every now and then due to how incredibly smooth the ninja rope now is. (especially on 144 Hz, but even on just 60 Hz the difference is huge)
Also, Deadcode isn't stopping any time soon and is expecting to start pushing many smaller updates that will take months rather than years.

Also, as announced previously on Discord, I will be sponsoring several Worms contests after the release of 3.8:

• Worms Scheme Contest 2020 - starting with a $200 prize pool with the possibility of more contributions
• Worm Olympics (Summer/Fall/Winter - TBD) - there will be a prize pool and everyone will be able to win a % based on performance. The tournament will feature brand-new schemes from 3.8. More details later when it's 100% finalized.

Wait until 3.8.