Better support for tmux

[marcdumais-work]

"Tmux is a software application that can be used to multiplex several virtual consoles, allowing a user to access multiple separate terminal sessions inside a single terminal window or remote terminal session."

It seems that tmux would be a useful tool to use within the Theia terminal. However at the moment, there are some things that do not work:

• selection seems broken.
• probably related, the browser's copy action is often not enabled when something is selected
• when by chance the copy action is enabled, what gets copied is not what's currently selected.

I have tried tmux in the xterm.js demo application and the above problems are not present.

[marcdumais-work]

BTW, it seems that tmux works fine in VS Code's terminal, at least for the simple use-case of selecting some text, copying it and pasting it.

[simark]

I was stepping side by side the xterm.js code, both in Theia and the xterm.js example (cloned from their git repo) and found that the code was a bit different. I realized that the example of xterm.js is based on the future major version (3.x.y), since that is the default branch of their git repo. In that branch, there are a few fixes related to tmux. So I tried to upgrade to use that version of xterm.js, and it seems to work better.

You can try the branch xterm.js-v3 in my repo: https://github.com/simark/theia/tree/xterm.js-v3

[simark]

vscode uses this branch of xterm.js, which seems based on v3 (note the merge commits from origin/v3 into that branch), so it would explain why it works there.

https://github.com/Tyriar/xterm.js/commits/vscode-release/1.18

[simark]

In the xterm.js-v3 Theia branch, I modified the Dockerfile in examples/browser to use that branch, so you can use it for testing.

[hexa00]

Can we use than branch from npm ? Is there a pre-release ?

[simark]

I don't think there's any packaged pre-release. If we really wanted to, I guess we could use xterm.js from the v3 git branch.

[hexa00]

If it works with v3 I think we could package it and use it

[simark]

Or just use vscode's branch :)

[hexa00]

I guess, it has 27 commits ahead of master.. not sure what it contains of it has as vscode specific stuff in there.