When output is redirected, terminal capabilities are ignored and colors are illegible

[AndydeCleyre]

Describe the bug
When output is redirected/piped, terminal capabilities are ignored and colors are illegible.

Setup

• Ubuntu 22.04 LTS
• Zsh
• Wezterm
• tmux
• en_US.UTF-8

To Reproduce

1. Given a markdown README.md . . .
2. Run:

$ CLICOLOR_FORCE=1 glow --style dark README.md | head

Source Code

Sample README

Expected behavior

The colors should be the same as they are when | head is omitted, and the header titles should have enough contrast to be easily read.

Screenshots

Additional context

See discussion at #440 (comment)

[meowgorithm]

Thanks for the excellent report. As mentioned, this looks like a regression. Off the cuff I'd guess it's downsampling to 4-bit ANSI (i.e. the 16 user-definable terminal colors; the first two rows in the following chart).

[folliehiyuki]

It's the behavior of termenv, which glow uses. See https://github.com/muesli/termenv/blob/82936c5ea257b458deb5238e6093773b42c43773/termenv.go#L104.

In short, when being piped, it detects that no terminal capabilities are available, hence no color profile will be chosen. If you force the color output with CLICOLOR_FORCE=1 when no color profile is detected, it will fallback to 4-color ANSI.

[meowgorithm]

Aha, there we have it. Technically speaking CLICOLOR_FORCE=1 COLORTERM=truecolor glow-s dark filename.md | head should work, but it looks like it may have regressed upstream.

Alternatively, we could introduce a flag like glow --force-color-profile.

glow --force-color-profile=truecolor
glow --force-color-profile=ansi256
glow --force-color-profile=ansi
glow --force-color-profile=notty

[Chaitanyabsprip]

instead of the --force-color-profile flag, just use whatever value COLORTERM env var contains

[meowgorithm]

That’s fine by me, but termenv will need to be corrected upstream.

[nikelborm]

#21 (comment)

script -q -c "glow README.md" | tail -n +2

[nikelborm]

After some digging, I found something interesting.

bash -c "echo date_before_script: \$(date); script -q -c 'echo date_before_glow: \$(date); glow README.md; echo date_after_glow: \$(date)' > temp; cat temp; echo date_after_script: \$(date)" > temp2

Instead of > temp2 in the end you can use | sed '3d' to remove bad line and

with following README.md:

# header

1. _something_
2. *bold*

temp2 looks like this:

date_before_script: Mon Nov 11 04:22:13 MSK 2024
date_before_glow: Mon Nov 11 04:22:13 MSK 2024
�]10;?�\�[6n�]11;?�\�[6n�]11;?�\�[6n
�[38;5;228;48;5;63;1m�[0m�[38;5;228;48;5;63;1m�[0m  �[38;5;228;48;5;63;1m �[0m�[38;5;228;48;5;63;1mheader�[0m�[38;5;228;48;5;63;1m �[0m�[38;5;252m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[0m
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�[38;5;252m�[0m�[38;5;252m�[0m  �[38;5;252m1�[0m�[38;5;252m. �[0m�[38;5;252;3msomething�[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m
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date_after_glow: Mon Nov 11 04:22:28 MSK 2024
date_after_script: Mon Nov 11 04:22:28 MSK 2024

Pairs of dates are exactly the same. Long execution is glow's or some other internally used library's responsibility. And for me it's always exactly 15 f***ing seconds. TTY is allocated immediately. And first line, that breaks output, is printed by glow too.

@eric-saintetienne (pinging because I think you'll be interested about it too because you did the same stuff here: #21 (comment))

I tried tracing the program. I created following script:

#!/bin/bash

/bin/bash -c "echo date_before_script: \$(/sbin/date); /sbin/script -q -c 'echo date_before_glow: \$(/sbin/date); SHLVL=1 COLUMNS=180 LINES=49 /sbin/glow README.md; echo date_after_glow: \$(/sbin/date)' > temp; /sbin/cat temp; echo date_after_script: \$(/sbin/date)" > temp2

And then I'm running it

sudo strace ./sh

What I get

trace log

execve("./sh", ["./sh"], 0x7ffcd70817c0 /* 17 vars */) = 0
brk(NULL)                               = 0x5ae528cfd000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=194599, ...}) = 0
mmap(NULL, 194599, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a28493000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/libreadline.so.8", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\0\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=343064, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x758a28491000
mmap(NULL, 350904, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x758a2843b000
mmap(0x758a28450000, 188416, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x15000) = 0x758a28450000
mmap(0x758a2847e000, 36864, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x43000) = 0x758a2847e000
mmap(0x758a28487000, 36864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4b000) = 0x758a28487000
mmap(0x758a28490000, 2744, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x758a28490000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\340_\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
fstat(3, {st_mode=S_IFREG|0755, st_size=2014520, ...}) = 0
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
mmap(NULL, 2034616, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x758a2824a000
mmap(0x758a2826e000, 1511424, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x24000) = 0x758a2826e000
mmap(0x758a283df000, 319488, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x195000) = 0x758a283df000
mmap(0x758a2842d000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e3000) = 0x758a2842d000
mmap(0x758a28433000, 31672, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x758a28433000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/libncursesw.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\0\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=453896, ...}) = 0
mmap(NULL, 453856, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x758a281db000
mmap(0x758a281e8000, 290816, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xd000) = 0x758a281e8000
mmap(0x758a2822f000, 90112, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x54000) = 0x758a2822f000
mmap(0x758a28245000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6a000) = 0x758a28245000
close(3)                                = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x758a281d9000
arch_prctl(ARCH_SET_FS, 0x758a281d9b80) = 0
set_tid_address(0x758a281d9e50)         = 338133
set_robust_list(0x758a281d9e60, 24)     = 0
rseq(0x758a281da4a0, 0x20, 0, 0x53053053) = 0
mprotect(0x758a2842d000, 16384, PROT_READ) = 0
mprotect(0x758a28245000, 16384, PROT_READ) = 0
mprotect(0x758a28487000, 12288, PROT_READ) = 0
mprotect(0x5ae513c4d000, 12288, PROT_READ) = 0
mprotect(0x758a284fd000, 8192, PROT_READ) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
munmap(0x758a28493000, 194599)          = 0
openat(AT_FDCWD, "/dev/tty", O_RDWR|O_NONBLOCK) = 3
close(3)                                = 0
getrandom("\x9f\x6e\x12\xb3\x3b\xe2\x4e\x66", 8, GRND_NONBLOCK) = 8
brk(NULL)                               = 0x5ae528cfd000
brk(0x5ae528d1e000)                     = 0x5ae528d1e000
openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=3055776, ...}) = 0
mmap(NULL, 3055776, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a27e00000
close(3)                                = 0
openat(AT_FDCWD, "/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=2998, ...}) = 0
read(3, "# Locale name alias data base.\n#"..., 4096) = 2998
read(3, "", 4096)                       = 0
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_IDENTIFICATION", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_IDENTIFICATION", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=258, ...}) = 0
mmap(NULL, 258, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284c2000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/gconv/gconv-modules.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=27010, ...}) = 0
mmap(NULL, 27010, PROT_READ, MAP_SHARED, 3, 0) = 0x758a284bb000
close(3)                                = 0
futex(0x758a2843272c, FUTEX_WAKE_PRIVATE, 2147483647) = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_MEASUREMENT", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MEASUREMENT", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=23, ...}) = 0
mmap(NULL, 23, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284ba000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_TELEPHONE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_TELEPHONE", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=47, ...}) = 0
mmap(NULL, 47, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b9000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_ADDRESS", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_ADDRESS", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=127, ...}) = 0
mmap(NULL, 127, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b8000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_NAME", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_NAME", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=62, ...}) = 0
mmap(NULL, 62, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b7000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_PAPER", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_PAPER", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=34, ...}) = 0
mmap(NULL, 34, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b6000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_MESSAGES", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MESSAGES", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFDIR|0755, st_size=30, ...}) = 0
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MESSAGES/SYS_LC_MESSAGES", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=48, ...}) = 0
mmap(NULL, 48, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b5000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_MONETARY", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_MONETARY", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=270, ...}) = 0
mmap(NULL, 270, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b4000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_COLLATE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_COLLATE", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=1406, ...}) = 0
mmap(NULL, 1406, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b3000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_TIME", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_TIME", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=3360, ...}) = 0
mmap(NULL, 3360, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b2000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_NUMERIC", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_NUMERIC", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=50, ...}) = 0
mmap(NULL, 50, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a284b1000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib/locale/C.UTF-8/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/usr/lib/locale/C.utf8/LC_CTYPE", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=360460, ...}) = 0
mmap(NULL, 360460, PROT_READ, MAP_PRIVATE, 3, 0) = 0x758a28180000
close(3)                                = 0
getuid()                                = 0
getgid()                                = 0
geteuid()                               = 0
getegid()                               = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigaction(SIGCHLD, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGCHLD, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x758a282871d0}, 8) = 0
rt_sigaction(SIGINT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGINT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
rt_sigaction(SIGQUIT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGQUIT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
rt_sigaction(SIGTSTP, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGTSTP, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
rt_sigaction(SIGTTIN, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGTTIN, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
rt_sigaction(SIGTTOU, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, 8) = 0
rt_sigaction(SIGTTOU, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigaction(SIGQUIT, {sa_handler=SIG_IGN, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
uname({sysname="Linux", nodename="archhost", ...}) = 0
getcwd("/tmp/tmp.zGlsz5be5c", 4096)     = 20
getpid()                                = 338133
getppid()                               = 338130
getpid()                                = 338133
getppid()                               = 338130
getpid()                                = 338133
getppid()                               = 338130
getpgrp()                               = 338130
ioctl(2, TIOCGPGRP, [338130])           = 0
rt_sigaction(SIGCHLD, {sa_handler=0x5ae513b93a60, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART, sa_restorer=0x758a282871d0}, 8) = 0
prlimit64(0, RLIMIT_NPROC, NULL, {rlim_cur=54025, rlim_max=54025}) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
openat(AT_FDCWD, "./sh", O_RDONLY)      = 3
newfstatat(AT_FDCWD, "./sh", {st_mode=S_IFREG|0755, st_size=289, ...}, 0) = 0
ioctl(3, TCGETS, 0x7ffd50ed22c0)        = -1 ENOTTY (Inappropriate ioctl for device)
lseek(3, 0, SEEK_CUR)                   = 0
read(3, "#!/bin/bash\n\n\n/bin/bash -c \"echo"..., 80) = 80
lseek(3, 0, SEEK_SET)                   = 0
prlimit64(0, RLIMIT_NOFILE, NULL, {rlim_cur=1024, rlim_max=512*1024}) = 0
fcntl(255, F_GETFD)                     = -1 EBADF (Bad file descriptor)
dup2(3, 255)                            = 255
close(3)                                = 0
fcntl(255, F_SETFD, FD_CLOEXEC)         = 0
fcntl(255, F_GETFL)                     = 0x8000 (flags O_RDONLY|O_LARGEFILE)
fstat(255, {st_mode=S_IFREG|0755, st_size=289, ...}) = 0
lseek(255, 0, SEEK_CUR)                 = 0
read(255, "#!/bin/bash\n\n\n/bin/bash -c \"echo"..., 289) = 289
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigprocmask(SIG_BLOCK, [INT TERM CHLD], [], 8) = 0
clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x758a281d9e50) = 338134
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGINT, {sa_handler=0x5ae513b961e0, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 338134
rt_sigaction(SIGINT, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=0x5ae513b961e0, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
ioctl(2, TIOCGWINSZ, {ws_row=78, ws_col=288, ws_xpixel=3456, ws_ypixel=2106}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=338134, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
wait4(-1, 0x7ffd50ed1210, WNOHANG, NULL) = -1 ECHILD (No child processes)
rt_sigreturn({mask=[]})                 = 0
read(255, "", 289)                      = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
exit_group(0)                           = ?
+++ exited with 0 +++

The most important part is where and how it hangs:

rt_sigaction(SIGINT, {sa_handler=0x5ae513b961e0, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=SA_RESTORER, sa_restorer=0x758a282871d0}, 8) = 0
wait4(-1,

it hangs in this state with uncompleted line for 15 seconds. Here's the most interesting part. remember the trash line? Its three equal parts (�]11;?�\�[6n) are being printed with equal noticeable time intervals one by one.

That's how stuff appears in a temp file:

1. immediately after start file becomes:

date_before_glow: Mon Nov 11 05:19:21 MSK 2024
�]10;?�\�[6n

2. exactly after 5 second hanging file becomes:

date_before_glow: Mon Nov 11 05:25:08 MSK 2024
�]10;?�\�[6n�]11;?�\�[6n

3. exactly after another 5 second hanging file becomes:

date_before_glow: Mon Nov 11 05:25:08 MSK 2024
�]10;?�\�[6n�]11;?�\�[6n�]11;?�\�[6n

4. exactly after YET ANOTHER 5 second hanging file becomes:

date_before_glow: Mon Nov 11 05:28:21 MSK 2024
�]10;?�\�[6n�]11;?�\�[6n�]11;?�\�[6n
�[38;5;228;48;5;63;1m�[0m�[38;5;228;48;5;63;1m�[0m  �[38;5;228;48;5;63;1m �[0m�[38;5;228;48;5;63;1mheader�[0m�[38;5;228;48;5;63;1m �[0m�[38;5;252m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[0m
�[0m  �[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m
�[38;5;252m�[0m�[38;5;252m�[0m  �[38;5;252m1�[0m�[38;5;252m. �[0m�[38;5;252;3msomething�[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m
�[38;5;252m�[0m�[38;5;252m�[0m  �[38;5;252m2�[0m�[38;5;252m. �[0m�[38;5;252;3mbold�[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m�[38;5;252m �[0m

date_after_glow: Mon Nov 11 05:28:36 MSK 2024

Based on that, I conclude that it hangs each time AFTER it printed �]10;?�\�[6n. I don't know what's the f**k is going on. May be some kind of awaiting before output buffer filled, and flushing it when timeout expires? But why the f**k doesn't this shit appear in other case we run glow? 🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️

Also interesting observation:
I'm 99.99% sure that glow uses something similar with gh-cli under the hood to beatify Markdown. I went ahead and run the same test, but with a different command: gh repo view.
Guess how many �]11;?�\�[6n in it's output?

• 1

Guess how long it executes? 06:30:36 -- 06:30:42 (6 sec)

• 5 (seconds) * 1 (�]11;?�\�[6n) + 1 (second -- overhead to make a call to github API)

I tried to decode this ANSI code using this cheatsheet and this character inspector.
In the end this seems like a command, to make some kind of cursor shift and then to request cursor position (ESC[6n).

And probably this artifitial TTY takes too long to respond and is being cutoff on timeout? 🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️

Also I have a hypothesis about what's up with all the trash symbols being triggered by printing �]11;?�\�[6n -- I have no idea how ANSI works, but maybe that's the response with cursor position that was asked by ESC[6n? 🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️

Ideas?

[nikelborm]

Until the fix is made somewhere, you can just use bat
Prints more-less acceptable colored .md file.

bat --style=plain --color=always "$file"

[nikelborm]

If only there was a way to find and disable this cursor shift with following cursor position request... 😉😉

Would be nice if somebody from the team will help identify libraries or pieces of code playing the role here and how to disable them, so we will have a quite nice workaround 😉😉

Here are common libraries between GitHub CLI and Glow. I assume the stuff we're looking is inside one of them:

(click to expand)

• https://github.com/alecthomas/chroma
• https://github.com/aymanbagabas/go-osc52
• https://github.com/aymerick/douceur
• https://github.com/charmbracelet/glamour
• https://github.com/charmbracelet/lipgloss
• https://github.com/dlclark/regexp2
• https://github.com/fsnotify/fsnotify
• https://github.com/gorilla/css
• https://github.com/hashicorp/hcl
• https://github.com/inconshreveable/mousetrap
• https://github.com/lucasb-eyer/go-colorful
• https://github.com/magiconair/properties
• https://github.com/mattn/go-isatty
• https://github.com/mattn/go-runewidth
• https://github.com/microcosm-cc/bluemonday
• https://github.com/mitchellh/go-homedir
• https://github.com/mitchellh/mapstructure
• https://github.com/muesli/reflow
• https://github.com/muesli/termenv
• https://github.com/pelletier/go-toml
• https://github.com/rivo/uniseg
• https://github.com/spf13/afero
• https://github.com/spf13/cast
• https://github.com/spf13/cobra
• https://github.com/spf13/pflag
• https://github.com/spf13/viper
• https://github.com/subosito/gotenv
• https://github.com/yuin/goldmark
• https://github.com/yuin/goldmark-emoji
• https://golang.org/x/exp
• https://golang.org/x/net
• https://golang.org/x/sync
• https://golang.org/x/sys
• https://golang.org/x/term
• https://golang.org/x/text
• https://gopkg.in/ini.v1
• https://gopkg.in/yaml.v3

I assume (honestly nothing more that intuition) it's either muesli/reflow or muesli/termenv because the same issue (muesli/termenv#136) appears to be there.

[nikelborm]

My findings didn't end there.

I tried to create new theme based on https://github.com/charmbracelet/glamour/blob/master/styles/dark.json and run it with new theme. I changed all margin fields from 2 to 0.

Timing improved. Now it runs 5 seconds faster.

Before

time /bin/bash -c "echo date_before_script: \$(/sbin/date); /sbin/script -q -c 'echo date_before_glow: \$(/sbin/date); SHLVL=1 COLUMNS=180 LINES=49 /sbin/glow README.md; echo date_after_glow: \$(/sbin/date)' > temp; /sbin/cat temp; echo date_after_script: \$(/sbin/date)" > temp2

real	0m15.059s
user	0m0.021s
sys	0m0.015s

cat temp2 | sed '3d'

date_before_script: Sat Nov 16 00:06:52 MSK 2024
date_before_glow: Sat Nov 16 00:06:52 MSK 2024
   header                                                                         
                                                                                  
  1. something                                                                    
  2. bold                                                                         

date_after_glow: Sat Nov 16 00:07:07 MSK 2024
date_after_script: Sat Nov 16 00:07:07 MSK 2024

3rd line:

�]10;?�\�[6n�]11;?�\�[6n�]11;?�\�[6n

After

time /bin/bash -c "echo date_before_script: \$(/sbin/date); /sbin/script -q -c 'echo date_before_glow: \$(/sbin/date); SHLVL=1 COLUMNS=180 LINES=49 /sbin/glow -s ./mystyle.json README.md; echo date_after_glow: \$(/sbin/date)' > temp; /sbin/cat temp; echo date_after_script: \$(/sbin/date)" > temp2

real	0m10.054s
user	0m0.020s
sys	0m0.015s

cat temp2 | sed '3d'

date_before_script: Sat Nov 16 00:10:52 MSK 2024
date_before_glow: Sat Nov 16 00:10:52 MSK 2024
 header                                                                         
                                                                                
1. something                                                                    
2. bold                                                                         

date_after_glow: Sat Nov 16 00:11:02 MSK 2024
date_after_script: Sat Nov 16 00:11:02 MSK 2024

3rd line:

�]10;?�\�[6n�]11;?�\�[6n

Edited theme:

{
  "document": {
    "block_prefix": "\n",
    "block_suffix": "\n",
    "color": "252",
    "margin": 0
  },
  "block_quote": {
    "indent": 1,
    "indent_token": "│ "
  },
  "paragraph": {},
  "list": {
    "level_indent": 2
  },
  "heading": {
    "block_suffix": "\n",
    "color": "39",
    "bold": true
  },
  "h1": {
    "prefix": " ",
    "suffix": " ",
    "color": "228",
    "background_color": "63",
    "bold": true
  },
  "h2": {
    "prefix": "## "
  },
  "h3": {
    "prefix": "### "
  },
  "h4": {
    "prefix": "#### "
  },
  "h5": {
    "prefix": "##### "
  },
  "h6": {
    "prefix": "###### ",
    "color": "35",
    "bold": false
  },
  "text": {},
  "strikethrough": {
    "crossed_out": true
  },
  "emph": {
    "italic": true
  },
  "strong": {
    "bold": true
  },
  "hr": {
    "color": "240",
    "format": "\n--------\n"
  },
  "item": {
    "block_prefix": "• "
  },
  "enumeration": {
    "block_prefix": ". "
  },
  "task": {
    "ticked": "[✓] ",
    "unticked": "[ ] "
  },
  "link": {
    "color": "30",
    "underline": true
  },
  "link_text": {
    "color": "35",
    "bold": true
  },
  "image": {
    "color": "212",
    "underline": true
  },
  "image_text": {
    "color": "243",
    "format": "Image: {{.text}} →"
  },
  "code": {
    "prefix": " ",
    "suffix": " ",
    "color": "203",
    "background_color": "236"
  },
  "code_block": {
    "color": "244",
    "margin": 0,
    "chroma": {
      "text": {
        "color": "#C4C4C4"
      },
      "error": {
        "color": "#F1F1F1",
        "background_color": "#F05B5B"
      },
      "comment": {
        "color": "#676767"
      },
      "comment_preproc": {
        "color": "#FF875F"
      },
      "keyword": {
        "color": "#00AAFF"
      },
      "keyword_reserved": {
        "color": "#FF5FD2"
      },
      "keyword_namespace": {
        "color": "#FF5F87"
      },
      "keyword_type": {
        "color": "#6E6ED8"
      },
      "operator": {
        "color": "#EF8080"
      },
      "punctuation": {
        "color": "#E8E8A8"
      },
      "name": {
        "color": "#C4C4C4"
      },
      "name_builtin": {
        "color": "#FF8EC7"
      },
      "name_tag": {
        "color": "#B083EA"
      },
      "name_attribute": {
        "color": "#7A7AE6"
      },
      "name_class": {
        "color": "#F1F1F1",
        "underline": true,
        "bold": true
      },
      "name_constant": {},
      "name_decorator": {
        "color": "#FFFF87"
      },
      "name_exception": {},
      "name_function": {
        "color": "#00D787"
      },
      "name_other": {},
      "literal": {},
      "literal_number": {
        "color": "#6EEFC0"
      },
      "literal_date": {},
      "literal_string": {
        "color": "#C69669"
      },
      "literal_string_escape": {
        "color": "#AFFFD7"
      },
      "generic_deleted": {
        "color": "#FD5B5B"
      },
      "generic_emph": {
        "italic": true
      },
      "generic_inserted": {
        "color": "#00D787"
      },
      "generic_strong": {
        "bold": true
      },
      "generic_subheading": {
        "color": "#777777"
      },
      "background": {
        "background_color": "#373737"
      }
    }
  },
  "table": {},
  "definition_list": {},
  "definition_term": {},
  "definition_description": {
    "block_prefix": "\n🠶 "
  },
  "html_block": {},
  "html_span": {}
}

It is definitely faster and definitely because of reducing amount of escape sequences which are being attempted to be printed by glow.

[nikelborm]

Next I'm gonna look for how margin is used and can we remove 2 ANSI sequences left