---
title: Grey background issue with Helix inside Byobu
date: 2025-02-10 09:58:10.144898 UTC
---
I often work on a remote Linux box and like to have [Byobu](https://www.byobu.org/) running so that I have tab view and status bar. But somedays in mid 2024, somethings start to break when I open Helix inside Byobu and get this annoying gray background every where:

![Grey background](https://quan-images.b-cdn.net/blogs/imgur/2026/BUeD20a.png)

The root issue is that, Byobu runs Tmux with a configuration, and that configuration makes tmux disable some features which is needed to render Helix theme correctly. The key is the `TERM` environment variable. No matter which terminal emulator we use, after running Byobu, the `TERM` is set to `screen-256color`.

```console
❯ echo $TERM
screen-256color
```

The good `TERM` value to prevent that background issue is `xterm-256color` or any `xterm-xxx`. Byobu comes with a bunch of Tmux configuration files that are foreign to me.

I found the line which indirectly modifies the `TERM` variable. It is in */usr/share/byobu/profiles/tmux* file:

```
set -g default-terminal "$BYOBU_TERM"
```

but I don't want to modify this file, because it will be overwritten if we update Byobu.

After some times doing trial and errors, I came up with a simple solution, that is to add this line to *~/.config/byobu/backend* (or *~/.byobu/backend*, if your server was installed from very old Ubuntu and upgraded version by version):

```sh
BYOBU_TERM=xterm-256color
```

After exitting Byobu and run again, Helix render correctly:

![Normal background](https://quan-images.b-cdn.net/blogs/imgur/2026/xcuzb8t.png)

Note, you can also use this:

```sh
BYOBU_TERM=$TERM
```
to let Byobu retains the same value of `TERM` as before it was running.