Prevent Gum v2 spinner capability replies from leaking
Author: lovatoCreated Aug 22, 2026Updated Sep 11, 2026
Description
Description
After upgrading to Gum v2.0.0, gum spin can display raw terminal capability replies in an interactive Bash session:
Searching packages...^[[?2026;2$y^[[?2027;3$y
The command still completes successfully, but the raw sequences corrupt the spinner/status output.
Steps to reproduce
gum --version
# gum version v2.0.0
gum spin --title "Searching packages..." -- sleep 3
Expected behavior
The spinner and title render without terminal control responses appearing as text.
Actual behavior
The terminal displays DEC mode 2026/2027 capability replies, such as:
^[[?2026;2$y^[[?2027;3$y
Environment
- Linux
- Interactive Bash shell
- Gum v2.0.0
- Standard terminal session, not redirected and not CI
Additional context
The sequences appear related to Gum v2's DEC mode 2026/2027 negotiation. A wrapper around gum spin can avoid the issue by using a plain status line, but Gum itself should consume or avoid exposing these replies.
Version
gum version v2.0.0 (4d089f9)
Environment
WSL/Linux/Debian Trixie
Source: charmbracelet/gum