Add text to avoid empty input for input workaround

[soraxas]

For the input workaround, we add a space key event to input some text before pressing the enter key. This avoid the error that happens due to gtk preventing empty input.

This make it so that the workaround works in gtk auth like:

Pretty much after the original workaround doesn't work, we will enter a space key before pressing enter

[soraxas]

closes #735