Support the hidden/conceal ansi escape

It's useful for hiding the output while it still occupies the space and is included when copy-pasting.

$ echo '\u001b[8mfoo\u001b[28mbar'
   bar

I'm specifically asking for support for the \u001b[8m (conceal) and \u001b[28m (unconceal) ansi escapes.

I personally use the conceal ansi escape in eslint-formatter-pretty to enable Cmd-clicking the title to go to the relevant line in the users editor without having to actually show the line in the output (it's concealed).

https://en.wikipedia.org/wiki/ANSI_escape_code

I think it should be supported as it's supported in other terminals like Terminal.app.

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• iTerm2 version: Build 2.9.20160421-nightly
• OS version: 10.11.4

Definitely agree on this one. Would be very nice if this was supported!

This would also helpful for triggers when executing long running processes remotely, eg, after building/compiling a large project remotely, display a notification locally via mac notifications or do any other geeky thing (firing lasers!).

Milestone changed to Feature Complete 3.1

Milestone changed to Feature Complete 3.2

Just FYI: In xterm these chars are not included when copy-pasting, they are replaced by spaces.

In all other terminal emulators that I could try now on Linux and do support this escape sequence (namely vte, st, terminology) these chars get properly copy-pasted. (I don't have a Mac now to test Terminal.app.)