Tmux pane content gets garbled after refreshing tmux client

[abhirup-dev]

Environment

Windows build number: 19041
Windows Terminal version: 0.7.3
tmux: 2.6

Steps to reproduce

1. Run command such as htop, top inside a tmux pane
2. Press Prefix + r (:refresh-client) to refresh the tmux client
   (I actually faced this problem during the course of my but was later able to reproduce it using steps 1 and 2.

Expected behavior

Nothing should happen. The command mentioned in step 1 should continue to run without any changes. In fact, that is what happens in minTTY terminal that ships by default with WSL.

Actual behavior

The output from htop gets garbled. Only the changing parts of the text, like fluctuating RAM usage, reordering of processes gets reflected. See the given screenshots in this Reddit post.

[zadjii-msft]

This is curious - I can't seem to repro this:

No matter how many times I tried, refresh-client didn't seem to corrupt the display at all.

Perhaps there's something more about your machine's config that's causing this. What's TERM set to? Which linux distro is this?

[abhirup-dev]

Within tmux, $TERM is set to "screen". Outside tmux, it is set to "xterm-256color". I'm using Ubuntu 1804.

No matter how many times I tried, refresh-client didn't seem to corrupt the display at all.

I'm able to reproduce this issue every time.

[zadjii-msft]

@maverickdas There must be something specific to your setup then that's causing this, because I still can't get this to repro.

1. What's the output of infocmp from within tmux?
2. What font are you using?
3. Which distro are you using?
4. Could you share your .tmux.conf?

[abhirup-dev]

What's the output of infocmp from within tmux?

#       Reconstructed via infocmp from file: /lib/terminfo/s/screen
screen|VT 100/ANSI X3.64 virtual terminal,
        am, km, mir, msgr, xenl,
        colors#8, cols#80, it#8, lines#24, ncv@, pairs#64,
        acsc=++\,\,--..00``aaffgghhiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~,
        bel=^G, blink=\E[5m, bold=\E[1m, cbt=\E[Z, civis=\E[?25l,
        clear=\E[H\E[J, cnorm=\E[34h\E[?25h, cr=\r,
        csr=\E[%i%p1%d;%p2%dr, cub=\E[%p1%dD, cub1=^H,
        cud=\E[%p1%dB, cud1=\n, cuf=\E[%p1%dC, cuf1=\E[C,
        cup=\E[%i%p1%d;%p2%dH, cuu=\E[%p1%dA, cuu1=\EM,
        cvvis=\E[34l, dch=\E[%p1%dP, dch1=\E[P, dim=\E[2m,
        dl=\E[%p1%dM, dl1=\E[M, ed=\E[J, el=\E[K, el1=\E[1K,
        enacs=\E(B\E)0, flash=\Eg, home=\E[H, hpa=\E[%i%p1%dG,
        ht=^I, hts=\EH, ich=\E[%p1%d@, il=\E[%p1%dL, il1=\E[L,
        ind=\n, indn=\E[%p1%dS, is2=\E)0, kbs=^?, kcbt=\E[Z,
        kcub1=\EOD, kcud1=\EOB, kcuf1=\EOC, kcuu1=\EOA,
        kdch1=\E[3~, kend=\E[4~, kf1=\EOP, kf10=\E[21~,
        kf11=\E[23~, kf12=\E[24~, kf2=\EOQ, kf3=\EOR, kf4=\EOS,
        kf5=\E[15~, kf6=\E[17~, kf7=\E[18~, kf8=\E[19~, kf9=\E[20~,
        khome=\E[1~, kich1=\E[2~, kmous=\E[M, knp=\E[6~, kpp=\E[5~,
        nel=\EE, op=\E[39;49m, rc=\E8, rev=\E[7m, ri=\EM, rmacs=^O,
        rmcup=\E[?1049l, rmir=\E[4l, rmkx=\E[?1l\E>, rmso=\E[23m,
        rmul=\E[24m, rs2=\Ec\E[?1000l\E[?25h, sc=\E7,
        setab=\E[4%p1%dm, setaf=\E[3%p1%dm,
        sgr=\E[0%?%p6%t;1%;%?%p1%t;3%;%?%p2%t;4%;%?%p3%t;7%;%?%p4%t;5%;%?%p5%t;2%;m%?%p9%t\016%e\017%;,
        sgr0=\E[m\017, smacs=^N, smcup=\E[?1049h, smir=\E[4h,
        smkx=\E[?1h\E=, smso=\E[3m, smul=\E[4m, tbc=\E[3g,
        vpa=\E[%i%p1%dd,

What font are you using?

I'm using Source Code Pro font and acrylicOpacity is true.

Which distro are you using?

Ubuntu 1804. kernel - 4.19.84

Could you share your .tmux.conf?

Here

[DHowett-MSFT]

Would you mind also sharing the output of infocmp outside of tmux? Thanks!

[abhirup-dev]

Output of infocmp from outside tmux:

#       Reconstructed via infocmp from file: /lib/terminfo/x/xterm-256color
xterm-256color|xterm with 256 colors,
        am, bce, ccc, km, mc5i, mir, msgr, npc, xenl,
        colors#0x100, cols#80, it#8, lines#24, pairs#0x7fff,
        acsc=``aaffggiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~,
        bel=^G, blink=\E[5m, bold=\E[1m, cbt=\E[Z, civis=\E[?25l,
        clear=\E[H\E[2J, cnorm=\E[?12l\E[?25h, cr=\r,
        csr=\E[%i%p1%d;%p2%dr, cub=\E[%p1%dD, cub1=^H,
        cud=\E[%p1%dB, cud1=\n, cuf=\E[%p1%dC, cuf1=\E[C,
        cup=\E[%i%p1%d;%p2%dH, cuu=\E[%p1%dA, cuu1=\E[A,
        cvvis=\E[?12;25h, dch=\E[%p1%dP, dch1=\E[P, dim=\E[2m,
        dl=\E[%p1%dM, dl1=\E[M, ech=\E[%p1%dX, ed=\E[J, el=\E[K,
        el1=\E[1K, flash=\E[?5h$<100/>\E[?5l, home=\E[H,
        hpa=\E[%i%p1%dG, ht=^I, hts=\EH, ich=\E[%p1%d@,
        il=\E[%p1%dL, il1=\E[L, ind=\n, indn=\E[%p1%dS,
        initc=\E]4;%p1%d;rgb\:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\E\\,
        invis=\E[8m, is2=\E[!p\E[?3;4l\E[4l\E>, kDC=\E[3;2~,
        kEND=\E[1;2F, kHOM=\E[1;2H, kIC=\E[2;2~, kLFT=\E[1;2D,
        kNXT=\E[6;2~, kPRV=\E[5;2~, kRIT=\E[1;2C, kb2=\EOE, kbs=^?,
        kcbt=\E[Z, kcub1=\EOD, kcud1=\EOB, kcuf1=\EOC, kcuu1=\EOA,
        kdch1=\E[3~, kend=\EOF, kent=\EOM, kf1=\EOP, kf10=\E[21~,
        kf11=\E[23~, kf12=\E[24~, kf13=\E[1;2P, kf14=\E[1;2Q,
        kf15=\E[1;2R, kf16=\E[1;2S, kf17=\E[15;2~, kf18=\E[17;2~,
        kf19=\E[18;2~, kf2=\EOQ, kf20=\E[19;2~, kf21=\E[20;2~,
        kf22=\E[21;2~, kf23=\E[23;2~, kf24=\E[24;2~,
        kf25=\E[1;5P, kf26=\E[1;5Q, kf27=\E[1;5R, kf28=\E[1;5S,
        kf29=\E[15;5~, kf3=\EOR, kf30=\E[17;5~, kf31=\E[18;5~,
        kf32=\E[19;5~, kf33=\E[20;5~, kf34=\E[21;5~,
        kf35=\E[23;5~, kf36=\E[24;5~, kf37=\E[1;6P, kf38=\E[1;6Q,
        kf39=\E[1;6R, kf4=\EOS, kf40=\E[1;6S, kf41=\E[15;6~,
        kf42=\E[17;6~, kf43=\E[18;6~, kf44=\E[19;6~,
        kf45=\E[20;6~, kf46=\E[21;6~, kf47=\E[23;6~,
        kf48=\E[24;6~, kf49=\E[1;3P, kf5=\E[15~, kf50=\E[1;3Q,
        kf51=\E[1;3R, kf52=\E[1;3S, kf53=\E[15;3~, kf54=\E[17;3~,
        kf55=\E[18;3~, kf56=\E[19;3~, kf57=\E[20;3~,
        kf58=\E[21;3~, kf59=\E[23;3~, kf6=\E[17~, kf60=\E[24;3~,
        kf61=\E[1;4P, kf62=\E[1;4Q, kf63=\E[1;4R, kf7=\E[18~,
        kf8=\E[19~, kf9=\E[20~, khome=\EOH, kich1=\E[2~,
        kind=\E[1;2B, kmous=\E[M, knp=\E[6~, kpp=\E[5~,
        kri=\E[1;2A, mc0=\E[i, mc4=\E[4i, mc5=\E[5i, meml=\El,
        memu=\Em, oc=\E]104\007, op=\E[39;49m, rc=\E8,
        rep=%p1%c\E[%p2%{1}%-%db, rev=\E[7m, ri=\EM,
        rin=\E[%p1%dT, ritm=\E[23m, rmacs=\E(B, rmam=\E[?7l,
        rmcup=\E[?1049l\E[23;0;0t, rmir=\E[4l, rmkx=\E[?1l\E>,
        rmm=\E[?1034l, rmso=\E[27m, rmul=\E[24m,
        rs1=\Ec\E]104\007, rs2=\E[!p\E[?3;4l\E[4l\E>, sc=\E7,
        setab=\E[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;5;%p1%d%;m,
        setaf=\E[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m,
        sgr=%?%p9%t\E(0%e\E(B%;\E[0%?%p6%t;1%;%?%p5%t;2%;%?%p2%t;4%;%?%p1%p3%|%t;7%;%?%p4%t;5%;%?%p7%t;8%;m,
        sgr0=\E(B\E[m, sitm=\E[3m, smacs=\E(0, smam=\E[?7h,
        smcup=\E[?1049h\E[22;0;0t, smir=\E[4h, smkx=\E[?1h\E=,
        smm=\E[?1034h, smso=\E[7m, smul=\E[4m, tbc=\E[3g,
        u6=\E[%i%d;%dR, u7=\E[6n, u8=\E[?%[;0123456789]c,
        u9=\E[c, vpa=\E[%i%p1%dd,

[andreibosco]

I'm also having this issue with tmux, but it doesn't happen with only htop. Example: If I split tmux vertically and move to the new panel the bottom area of the terminal starts getting garbled.

[DHowett]

Fortunately, that one doesn't matter!

[edrpls]

Not sure if this would help debug the issue, but I just noticed that floating windows in neovim inside tmux also suffer from a similar issue, where part of them will be rendered on the left side of the terminal.

When the floating window is closed, it leaves some artifacts behind at the edge of the screen:

This doesn't happen when running neovim outside tmux.

[fergalmoran]

@edrpls - this is fixed for me in the latest preview 1.1.1812.0

[edrpls]

Thanks @fergalmoran, I'll try that version.

[edrpls]

I have been testing out preview 1.1.1812.0, and while the issue is not as frequent, it still happens with vertical panes.

[DHowett]

Is the character still 0x0f when you’re seeing the issue with vertical panes?

[edrpls]

@DHowett I'm not sure, since it happens very rarely now, it's difficult to debug, so it's not that much of an issue now. I'll try to get more data if next time it happens.

[Jessidhia]

A similar thing that is hard to consistently reproduce it, and very difficult to actually get a screenshot of it; but sometimes (tmux 3.0a in Terminal 1.3.2382.0), when mouse mode is enabled*, opening the right click menu (holding right mouse button wherever) will draw all the line drawing characters with garbled characters; they look very similar to UTF-8 text being parsed as ISO-8859-1. The terminal does correct itself very quickly, less than 100ms, but if the garbled characters did cause line wrapping to happen, the layout stays broken until one changes panes or tabs.

*: set -g mouse on, which can be input without changing your tmux.conf by using Ctrl+b :

When the garbled line drawing characters from the right click menu happen, any line drawing characters from pane separators will also be shown as random characters until tmux corrects itself.

Note that this is not due to tmux or something else in the system not being in UTF-8 mode; UTF-8 filenames are still correctly printed and displayed. It's only that split second frame that appears to incorrectly decode UTF-8. This also happens, sometimes, with my shell's powerline-based PS1 after starting tmux from scratch: the PS1 will print garbled text instead of powerline characters, and then it'll correct itself before I put any input; but if the extra length from the bad decode(?) causes a line wrap, the tmux status line gets pushed off-screen unless I detach and reattach.

---

EDIT: after the terminal was left attached overnight, this happened to the tmux status line:

The input cursor for the shell is also positioned incorrectly:

[Jessidhia]

I just happened to catch this same glitch happening while being completely outside tmux; this is just a regular direct zsh session in WSL2:

The glitch happened to coincide with me typing, which is possibly what caused the glitch to stay on screen.

[DHowett]

Whoa. It looks like something disabled UTF-8 handling. You're totally right about that. Tell me, is this under the MSYS2/Cygwin runtime?

[shuffle2]

Setting locale to en_US
with sudo update-locale LANG=en_US.UTF8
solved the problem for me.
Before there was C.UTF8

Just wanted to note that I was in the same situation and this also "fixed" it for me. Default install of Ubuntu 20.10 in WSL2, using Terminal 1.4.3243.0 from the Store. Before switching to en_US.UTF8 I would sometimes get corruption (mostly when color escape codes were used in weechat, or some combination of tmux, htop, etc).
It does seem like the default should "just work" - but is the issue with Terminal, WSL2's Ubuntu distro, or something else?

After changing to en_US.UFT8 there is still some improper behavior, e.g.:

(the "space" in "shuffle2" shouldn't be there)

With C.UTF8, the formatting of the blue URL would get broken and cause random other lines of the window to be overwritten.

The nickname is using a unicode zero-width space: https://github.com/dolphin-emu/sadm/blob/38433caf317fafb66c46efdbf6bed03fbf9d21c0/central/ircclient.py#L108

edit: actually, there is still some corruption (although not as bad).
A weechat channel with some lines containing escape codes:

After changing weechat window to view another channel, some characters remain on screen:

ok...last update 😅
After letting weechat run for some time, I am actually still seeing corruption close to or the same as before, so C.UTF8->en_US.UTF8 didn't help as much as I thought.
I also see that the zero-width unicode issue specifically is already tracked in a separate issue on this github repo.

[llchan]

This may be a red herring, but it seem that if I ssh to a host with an identical infocmp both inside + outside of tmux, rendering behaves normally --- this rendering issue only happens for me in a tmux running locally (WSL2).

[Gee19]

I haven't seen this issue for the past few months using preview builds but in the last few days it started happening consistently. Always the same setup, 2 horizontal tmux panes with vim in the top pane (split vertically).

This issue went away when I switched to the newest stable release (Windows Terminal v1.10.2714.0).

[l1n3n01z]

I have 1.11.3471.0
For the purposes of this test I used both Cascadia Mono and Consolas.
I can reproduce this problem simply by doing line selection in a clean neovim through tmux

[l1n3n01z]

I have 1.11.3471.0 For the purposes of this test I used both Cascadia Mono and Consolas. I can reproduce this problem simply by doing line selection in a clean neovim through tmux

This may be a tmux configuration issue. The problem seems to be fixed after I set
set-window-option -g utf8 on
in .tmux.conf
after seeing this issue kovidgoyal/kitty#2047

[glowinthedark]

Looks like that the corruption happens when the minute changes, so it's somehow related to the time display.

a few months later... — happened to have the same tmux session being displayed on two different screens from two different OS's and noticed that only the macos iTerm2 session was suffering from mangled display. Same session in Apple's ootb Terminal.apps is totally fine.

[zadjii-msft]

for x-linking purposes: #6987

[zadjii-msft]

Hey it's been years since we've heard anything about this - is anyone still hitting this on 1.22 Preview/? That version has a wholly re-written conpty that does away with a lot of old bugs

[l1n3n01z]

Hey it's been years since we've heard anything about this - is anyone still hitting this on 1.22 Preview/? That version has a wholly re-written conpty that does away with a lot of old bugs

I fixed the issue at the time by setting utf8 in tmux. I am using 1.22 and not getting any issues at all. I have had issues in other terminals (Alacritty and WezTerm) with weird fonts (half-width fonts and some other issues) that have left tmux garbled on Windows but not in Windows Terminal.

An aside, it would be really nice for the terminal ecosystem on windows, if the authors of those other terminals (and wsltty as well) had a better documented way of using conpty correctly. Usually when issues come up with other terminals, it's almost always windows specific and it's almost always because of incorrect conpty or incorrect use of conpty.

[microsoft-github-policy-service]

This issue has been automatically marked as stale because it has been marked as requiring author feedback but has not had any activity for 4 days. It will be closed if no further activity occurs within 3 days of this comment.