Fix frozen terminal caused by opener

[KlzXS]

xdg-open would launch a cli program that would contest the terminal for character input resulting in a unresponsive terminal that's hard to use. There are many references to this issue, but I'm bad at finding them.

If you send xdg-opens's std{in,out,err} to the shadow realm it seems to prevent it from launching cli programs (probably because they don't want to work without any I/O, but I guess you can may be able to find some oddballs) so it defaults to some gui program (probably firefox) and that doesn't block the terminal.

This should be tested to make sure the other openers are okay with silencing their std{in,out,err}.

[jarun]

@KlzXS can you share some test cases?

[KlzXS]

Right. I use LICENSE but any text/plain file should do. Just hover over it and press l or Enter to open it.
In my case it decides to open with vim for you it may be some other terminal editor or maybe even less depends on your configuration. Doesn't matter really, as long as it's a terminal program that accepts input from stdin the problem holds.

You won't see anything change but your keypresses will now be "ignored" at random, effectively making the terminal unusable.

[KlzXS]

I forgot to mention. Of course if you have it setup so that text/plain files are opened in a gui editor like sublime you won't be experiencing this with text files. Right now I can't think of a non-text file that is commonly opened in terminal, but any such would also exhibit this behavior.

[jarun]

Thank you!