Starting nvim-0.10 in docker crashes tmux

[joshuali925]

Problem

Starting nvim inside docker inside tmux crashes tmux. This seems wezterm specific, trying on default Mac terminal it does not happen.

Steps to reproduce

1. tmux (pre-installed version is 3.4)
2. install docker
3. docker run -it --rm ubuntu bash -c 'apt update; apt install -y wget; bash'
4. in docker, run wget https://github.com/neovim/neovim/releases/download/v0.10.0/nvim-linux64.tar.gz; tar xzf nvim-linux64.tar.gz; ./nvim-linux64/bin/nvim
5. see tmux crash with [server exited unexpectedly]

Expected behavior

same as 0.9.5 where it runs normally

Neovim version (nvim -v)

v0.10.0

Vim (not Nvim) behaves the same?

no, vim 9.1

Operating system/version

mac 13.6 ssh to Ubuntu 24.04 x64

Terminal name/version

wezterm 20240212-073805-217dfb30

$TERM environment variable

tmux-256color

Installation

tarball from github release

[wookayin]

Can you please attach tmux log if possible?

[zeertzjq]

Hmm, according to tmux/tmux#3983 this seems to happen because DECRQSS conflicts with tmux's handling of sixel, while detecting tmux in Docker using environment variables does not work.

[joshuali925]

tmux-logs.tar.gz

Also if i start tmux on Mac, then ssh and run nvim, tmux also crashes

[joshuali925]

I can confirm rebuilding tmux from HEAD on master branch fixes it.

On tmux 3.4 (host) setting the TMUX environment variable (in docker) before opening nvim could prevent crashing tmux, but setting TERM=tmux-256color does not work. I also tried to comment out tui_query_extended_underline(tui); but tmux still crashes, so I'm not sure if it's this

neovim/src/nvim/tui/tui.c

Line 1916 in 27fb629

bool tmux = terminfo_is_term_family(term, "tmux") || !!os_getenv("TMUX");

neovim/src/nvim/tui/tui.c

Lines 429 to 434 in 27fb629

	// Don't use DECRQSS in screen or tmux, as they behave strangely when receiving it.
	// Terminal.app also doesn't support DECRQSS.
	if (tui->unibi_ext.set_underline_style == -1 && !(screen || tmux || nsterm)) {
	// Query the terminal to see if it supports extended underline.
	tui_query_extended_underline(tui);
	}

[zeertzjq]

There is another use of DECRQSS in runtime/lua/vim/_defaults.lua

[GNITOAHC]

I use iterm2 + tmux version 3.4 on MacOS.
When ssh to a Ubuntu 22.04.4 LTS with nvim v0.10.0 it crash my tmux, too.

[splooge]

Similar issue

localhost$ tmux -V
tmux 3.4

localhost$ tmux -vvv
localhost$ ssh remotehost
remotehost$ nvim -v
NVIM v0.10.0
Build type: Release
LuaJIT 2.1.0-beta3
Run "nvim -V1 -v" for more info

remotehost$ nvim --clean
[server exited unexpectedly]

tmux-logs.tar.gz

[fallenbeck]

There is a fix on the tmux side:
tmux/tmux#3983