Tmux on new Mac won't interpret Ctrl+H

[unphased]

no amount of tweaking infocmp to kbs=\177 fixes the issue I'm having where ctrl+h bind gets ignore by tmux.

I have one computer that works fine (M1 Max MBP running Sonoma) and one computer I'm setting up (M4 Mini running Sequoia) that has the problem. I am going to post the relevant config and the relevant tmux server logs from both computers.

tmux config:

bind -n C-h display-message -p 'window_panes: #{window_panes} pane_title: #{pane_title}  match (N)VIM title: #{m/r:^N?VIM,#{pane_title}} zoomed: #{window_zoomed_flag} current_command: #{pane_current_command} final logic: #{||:#{==:1,#{window_panes}},#{||:#{m/r:^N?VIM,#{pane_title}},#{&&:#{window_zoomed_flag},#{==:ssh,#{pane_current_command}}}}}'

Sequoia machine tmux log:

1737678283.962091 /dev/ttys001: read 1 bytes (already 0)
1737678283.962135 /dev/ttys001: keys are 1 (\b)
1737678283.962146 /dev/ttys001: next key is 1 (\b) (expired=0)
1737678283.962152 /dev/ttys001: complete key \b 0x8
1737678283.962164 cmdq_append </dev/ttys001>: [server_client_key_callback/0x135804230]
1737678283.962171 cmdq_next <global>: empty
1737678283.962176 cmdq_next </dev/ttys001>: enter
1737678283.962181 cmdq_next </dev/ttys001>: [server_client_key_callback/0x135804230] (1), flags 0
1737678283.962186 session $0 0 activity 1737678283.962185
1737678283.962194 cmd_find_from_client: s=$0 0
1737678283.962198 cmd_find_from_client: wl=1 1 w=@0 zsh
1737678283.962202 cmd_find_from_client: wp=%0
1737678283.962206 cmd_find_from_client: idx=none
1737678283.962214 key table root (pane %0)
1737678283.962219 key table root (pane %0)
1737678283.962224 not found in key table root
1737678283.962229 writing key 0x8 ([BS]) to %0
1737678283.962233 input_key: \b
1737678283.962245 unref client 0x15500fc00 (2 references)
1737678283.962250 cmdq_next </dev/ttys001>: exit (empty)
1737678283.962254 cmdq_next <global>: empty
1737678283.962258 cmdq_next </dev/ttys001>: empty
1737678283.962264 server_client_reset_state: client /dev/ttys001 mode CURSOR,KCURSOR,KKEYPAD,WRAP,BRACKETPASTE
1737678283.962269 server_client_reset_state: cursor to 8,15
1737678283.962275 server_client_check_pane_buffer: pane %0 is on
1737678283.962279 server_client_check_pane_buffer: pane %1 is on
1737678283.962285 @0 active pane not changed
1737678283.962307 cmdq_next <global>: empty
1737678283.962316 cmdq_next </dev/ttys001>: empty
1737678283.962321 server_client_reset_state: client /dev/ttys001 mode CURSOR,KCURSOR,KKEYPAD,WRAP,BRACKETPASTE
1737678283.962325 server_client_reset_state: cursor to 8,15

Sonoma machine log:

1737678129.139423 /dev/ttys062: read 1 bytes (already 0)
1737678129.141599 /dev/ttys062: keys are 1 (\b)
1737678129.141663 /dev/ttys062: next key is 1 (\b) (expired=0)
1737678129.141677 /dev/ttys062: complete key \b 0x8
1737678129.141697 cmdq_append </dev/ttys062>: [server_client_key_callback/0x1491109d0]
1737678129.141708 cmdq_next <global>: empty
1737678129.141717 cmdq_next </dev/ttys062>: enter
1737678129.141728 cmdq_next </dev/ttys062>: [server_client_key_callback/0x1491109d0] (1), flags 0
1737678129.141740 session $0 0 activity 1737678129.141736 (last 1737678128.372226)
1737678129.141757 cmd_find_from_client: s=$0 0
1737678129.141768 cmd_find_from_client: wl=1 1 w=@0 zsh
1737678129.141775 cmd_find_from_client: wp=%0
1737678129.141784 cmd_find_from_client: idx=none
1737678129.141797 session 0 not pasting
1737678129.141808 key table root (pane %0)
1737678129.141819 found in key table root
1737678129.141858 cmdq_get_command: [if-shell/0x149110e60] group 3783
1737678129.141870 cmdq_insert_after </dev/ttys062>: [if-shell/0x149110e60] after [server_client_key_callback/0x1491109d0]
1737678129.141878 unref client 0x14980d800 (3 references)
1737678129.141888 cmdq_next </dev/ttys062>: [if-shell/0x149110e60] (0), flags 0
1737678129.141924 message: /dev/ttys062 key C-h: if-shell -F "#{||:#{==:1,#{window_panes}},#{||:#{m/r:^N?VIM,#{pane_title}},
#{&&:#{window_zoomed_flag},#{==:ssh,#{pane_current_command}}}}}" "send-keys C-h" "select-pane -L"
1737678129.141949 cmdq_fire_command </dev/ttys062>: (3783) if-shell -F "#{||:#{==:1,#{window_panes}},#{||:#{m/r:^N?VIM,#{pan
e_title}},#{&&:#{window_zoomed_flag},#{==:ssh,#{pane_current_command}}}}}" "send-keys C-h" "select-pane -L"
1737678129.141958 cmd_find_from_client: s=$0 0
1737678129.141965 cmd_find_from_client: wl=1 1 w=@0 zsh
1737678129.141972 cmd_find_from_client: wp=%0
1737678129.141979 cmd_find_from_client: idx=none
1737678129.141988 cmd_find_target: target none, type pane, item 0x149110e60, flags QUIET,CANFAIL
1737678129.141995 cmd_find_target: current is from queue
1737678129.142002 cmd_find_target: s=$0 0
1737678129.142010 cmd_find_target: wl=1 1 w=@0 zsh
1737678129.142016 cmd_find_target: wp=%0
1737678129.142023 cmd_find_target: idx=none
1737678129.142033 format_defaults: c=/dev/ttys062
1737678129.142040 format_defaults: s=$0
1737678129.142047 format_defaults: wl=1

Yep so the only sense I can make out of comparing these two logs is that on the offending computer we get the unexpected not found in key table root. Kind of stuck because I do not know where to look to figure out (aside from possibly infocmp kbs, and I am starting to feel like that is definitely not relevant) where the mapping is that tmux is supposed to be referencing to convert \b into c-h.

I understand that \b is supposed to indicate backspace, and that ctrl+h is the traditional backspace ascii character, and I'm fine with ctrl+h being interpreted by my shell as synonymous with backspace but I need to use it for directional left mnemonic functionality in line with h for left in the vim style.

I can clearly see that tmux passes the ctrl+h keystroke through to the child pane, which makes it clear that tmux is not doing anything like converting the ctrl+h into a ^? backspace, because that would cause an inner vim to backspace instead of ctrl+h. The problem here is that even though the C-h bind has been set in tmux config it is not triggering it.

infocmp $TERM from Sequoia machine:

#	Reconstructed via infocmp from file: /Users/slu/.terminfo/61/alacritty
alacritty|alacritty terminal emulator,
	am, bce, ccc, hs, km, mc5i, mir, msgr, npc, xenl,
	colors#256, cols#80, it#8, lines#24, pairs#32767,
	acsc=``aaffggiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz{{||}}~~,
	bel=^G, bold=\E[1m, cbt=\E[Z, civis=\E[?25l,
	clear=\E[H\E[2J, cnorm=\E[?12l\E[?25h, cr=^M,
	csr=\E[%i%p1%d;%p2%dr, cub=\E[%p1%dD, cub1=^H,
	cud=\E[%p1%dB, cud1=^J, 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, dsl=\E]2;\007, ech=\E[%p1%dX,
	ed=\E[J, el=\E[K, el1=\E[1K, flash=\E[?5h$<100/>\E[?5l,
	fsl=^G, home=\E[H, hpa=\E[%i%p1%dG, ht=^I, hts=\EH,
	ich=\E[%p1%d@, il=\E[%p1%dL, il1=\E[L, ind=^J,
	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=\177, 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,
	setb@, setf@,
	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,
	tsl=\E]2;, u6=\E[%i%d;%dR, u7=\E[6n,
	u8=\E[?%[;0123456789]c, u9=\E[c, vpa=\E[%i%p1%dd,

infocmp $TERM from Sonoma machine is identical. I confirmed it, so I don't need to paste it a second time.

[unphased]

Making a note of tmux commit, the one i am running on Sonoma is 109d2bda from 185 days ago. I built tmux from source on Sequoia machine a few weeks back and have been suffering from this issue since then. It is commit e75f3a00. Let me test building the newer commit on the working machine and see what that does.

[unphased]

problem CONFIRMED now I will test latest trunk

[unphased]

I built on the latest commit 6ab268c7 and expected functionality has been restored.