#1137270 libvte-2.91-0: Assertion auto_mode != eTTY failed in map_erase_binding.

Package:
libvte-2.91-0
Source:
libvte-2.91-0
Description:
Terminal emulator widget for GTK+ 3.0 - runtime files
Submitter:
John Doe
Date:
2026-05-28 16:33:02 UTC
Severity:
normal
#1137270#5
Date:
2026-05-21 21:05:21 UTC
From:
To:
Dear Maintainer,

On Debian Testing (Forky), running `vim` in virt-manager's Serial console causes virt-manager (python3) to crash with:

../src/vte.cc:5083: void vte::terminal::Terminal::map_erase_binding(EraseMode, EraseMode, unsigned int, char*&, size_t&, bool&, bool&): Assertion `auto_mode != eTTY' failed.

The crash happens after the ~ lines are drawn and during/after the color change from dark blue (34m) to light blue (94m), while Vim sends multiple DCS queries (\eP+qXXXX\e\).

Reproduction:
1. Open a VM in virt-manager → Serial console
2. Run: vim
3. Crash occurs reliably.

Workarounds:
- TERM=vt220 vim → no crash (but no colors)
- virsh console works fine (bypasses VTE)

I have attached a minimal C reproducer that triggers the same assertion by sending the relevant DCS queries after ~ lines + color change.
#1137270#10
Date:
2026-05-22 07:38:01 UTC
From:
To:
"\x1bP+q6b62\x1b\\"

This is the query to get key_backspace.
#1137270#15
Date:
2026-05-28 16:32:06 UTC
From:
To:
I reported this bug upstream
<https://gitlab.gnome.org/GNOME/vte/-/work_items/2952> and attached a
preliminary patch to fix it.