Many people these days got widescreen Monitors/TVs, so it would be nice if VBA-M had an option to not preserve aspect ratio. As you know GameBoy games can be very addictive, so if you play several hours this could also prevent the screen burn effect.

You can already do that.

Options -> Video -> Fullscreen -> Stretch to fit

It may be a bit misplaced, but I made it work for windowed mode as well as for fullscreen.
The "Max Scale..." might be interesting for you as well.

This option seems not available in the linux version. There is neither a commandline switch or a config entry. There is a 'borderOn' and a 'borderAutomatic' switch, but I could't figure what they do.

This will be available in the QT version, i hope you can wait patiently .

VBA-M | NGOHQ | Post Impact Productions | TNHW | XBCD 0.2.7

We got a fair bit of work to get done in regards to that.

Such as finalising the GUI options and wiring up the backend.....

Having a QT GUI is for sure a good thing, but will it be possible to set stretch mode per commandline switch / config file / key? In other words will the whole functionality of the backend be accessable without the GUI?

Oh and before forget, thanks for making this very nice crossplattform GameBoy emulator. I play Castlevania-AoS and it's great fun.