Cursor does not blink in Tmux after v2.9.0

[fengyichui]

Cursor does not blink in Tmux after v2.9.0, and v2.8.5 is good. I experience this problem under cygwin.

[mintty]

The culprit is the CSI escape sequence ESC[?12l which is supported since 2.9.0, following xterm.
It is included in the terminfo "cnorm" sequence to reset the cursor. Somebody probably put it in there on purpose.

Actually, behaviour is identical in xterm; this is not a mintty issue, so I'm marking it invalid.
A workaround is already available: include option SuppressDEC=12 in your config file.

[fengyichui]

oh, thanks

[mintty]

Actually there is one possible workaround that I've now implemented:
Blinking cursor mode (DECSET 12) effectively overlays blinking cursor style (DECSCUSR) so that DECRST 12 does not reset blinking but revert to the previous blinking style.

[mintty]

Released 3.0.1.

[solotim]

I'm using 3.5.0 mintty, but still have this issue.
I tried SuppressDEC=12 in my config, it doesn't work.
What else I should provide to help you diagnose the issue?
Thanks

[mintty]

As the original issue was identified and a workaround established two years ago, I'm not sure whether this is now still the same issue. Please describe steps to reproduce it in details. Also make a screen log (run mintty -l logfile until the issue occurs, then copy the logfile).

[solotim]

Thanks.

^[[?2004h^[]0;~^G^M
^[[32musera@PC-USERA ^[[35mMSYS^[[0m ^[[33m~^[[0m^M
$ ^M(reverse-i-search)`': ^H^H^Hs': ssh ^[[7ms^[[27momainx-usera^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^Hs': ^[[7mss^[[27mh domainx-usera^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^M^[[22P$ ss^H^H
^[[?2004l^M^Musera@domainx-usera's password:
Last login: Wed Nov 10 12:32:57 2021 from 10.208.184.17^M
^[[?1034h^[[?1034h^[[?1034h^[[?1034h^[[?1034h^[[?1034h^[]0;usera@domainx-usera: ~^G^[[01;32musera@domainx-usera^[[00m: ^[[01;90m~^[[00m
$ tmux ls
VM: 2 windows (created Sat Oct 23 19:55:45 2021)
^[]0;usera@domainx-usera: ~^G^[[01;32musera@domainx-usera^[[00m: ^[[01;90m~^[[00m
$ tmux a
^[[?1049h^[[?1h^[=^[[H^[[2J^[[?12l^[[?25h^[[?1000l^[[?1002l^[[?1003l^[[?1006l^[[?1005l^[(B^[[m^[[?12l^[[?25h^[[?1006l^[[?1000l^[[?1002l^[[?1003l^[[?2004l^[[1;1H^[[1;24r^[[>c^[[>q^[[2;3H^[[2 q^[[?12l^[[?25h^[]0;1:bash^G^[[?25l^[[36m^[[1m^[[Husera@hw746^[(B^[[m: ^[[90m^[[1m~^[(B^[[m^[[K
$ ^[[K
^[[K
^[[K
^[[K
^[[K
^[[K
^[[K
^[[K
^[[K
^[[K
^[[K
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^[[K
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^[[K^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m
 VM ^[[37m^[[48;5;88m-qv key-table) = 'off' ] && echo 'OFF'' not ready>^[[38;5;245m^[[48;5;232m  <'/home/usera/.tmux/pl^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[(B^[[m^[[?12l^[[?25h^[[?1006l^[[?1000l^[[?1002l^[[?1003l^[[?2004l^[[1;1H^[[1;24r^[[?25l^[[36m^[[1m^[[1;1Husera@hw746^[(B^[[m: ^[[90m^[[1m~^[(B^[[m^[[K
$ ^[[K
^[[K
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^[[K^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m
 VM ^[[37m^[[48;5;88m-qv key-table) = 'off' ] && echo 'OFF'' not ready>^[[38;5;245m^[[48;5;232m  <'/home/usera/.tmux/pl^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[?25l^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m^[[24;1H VM ^[[38;5;245m/plugins/tmux-plugin-sysstat/scripts/cpu.sh' not ready> | <'/home/usera/.t^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[?69h^[[?7727h^[[?69h^[[?7727h^[[1;24r^[[s^[[2;3H^[[?25l^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m^[[24;1H VM ^[[38;5;245msera/.tmux/plugins/tmux-plugin-sysstat/scripts/mem.sh' not ready> | 0.00 0^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[?25l^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m^[[24;1H VM ^[[38;5;220m%^[[38;5;245m | MEM:^[[38;5;76m33%^[[38;5;245m 1.2G | 0.00 0.01 0.21 | ^[[38;5;134musera^[[38;5;245m@domainx-usera | ^[[38;5;134mNov 10 12:33^[[38;5;245m    ^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[?25l^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m^[[24;1H VM ^[[38;5;76m%^[[38;5;245m | MEM:^[[38;5;76m33%^[[38;5;245m 1.2G | 0.00 0.01 0.21 | ^[[38;5;134musera^[[38;5;245m@domainx-usera | ^[[38;5;134mNov 10 12:33^[[38;5;245m    ^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[?25l^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m^[[24;1H VM ^[[38;5;76m%^[[38;5;245m | MEM:^[[38;5;76m33%^[[38;5;245m 1.2G | 0.00 0.01 0.21 | ^[[38;5;134musera^[[38;5;245m@domainx-usera | ^[[38;5;134mNov 10 12:33^[[38;5;245m    ^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[?25l^[[2 q^[[?25l^[[38;5;39m^[[48;5;232m^[[24;1H VM ^[[38;5;76m%^[[38;5;245m | MEM:^[[38;5;76m33%^[[38;5;245m 1.2G | 0.00 0.01 0.21 | ^[[38;5;134musera^[[38;5;245m@domainx-usera | ^[[38;5;134mNov 10 12:33^[[38;5;245m    ^[(B^[[m^[[?12l^[[?25h^[[2;3H^[[2 q^[[?12l^[[?25h^[[1;24r^[(B^[[m^[[?1l^[>^[[H^[[2J^[[2 q^[[?12l^[[?25h^[[?1000l^[[?1002l^[[?1003l^[[?1006l^[[?1005l^[[?7727l^[[?1004l^[[>4m^[[?69l^[[?1049l[detached (from session VM)]
^[]0;usera@domainx-usera: ~^G^[[01;32musera@domainx-usera^[[00m: ^[[01;90m~^[[00m
$ exit
logout
Connection to domainx-usera closed.^M
^[[?2004h^[]0;~^G^M
^[[32musera@PC-USERA ^[[35mMSYS^[[0m ^[[33m~^[[0m^M
$ exit
^[[?2004l^Mexit

[solotim]

The steps are simple:

1. Open mintty
2. ssh <host>
3. tmux a

After #2 is executed, the cursor now is in the remote host, blinking as normal, but after #3, the cursor stops blinking. Even if I detach the tmux, the blinking doesn't recover.

[mintty]

There are a number of escape sequences ^[[2 q in the log. This is DECSCUSR 2, set cursor style to steady block.
I cannot tell where they come from but it makes clear that the terminal behaviour is correct.