canonical/mir

Pointer/touchpad acceleration bias configuration values not loaded at startup

Open

#4,605 opened on Jan 7, 2026

View on GitHub
 (2 comments) (0 reactions) (0 assignees)C++ (137 forks)auto 404
Good first issue

Repository metrics

Stars
 (775 stars)
PR merge metrics
 (PR metrics pending)

Description

Version

v2.25.2

Environment

OS: Ubuntu 24.04

What happened? What did you expect to happen?

When using a live config file, pointer_acceleration_bias and touchpad_acceleration_bias (and maybe others) are not set at startup. If the file is modified then the values are set correctly. On the other hand keymap does get set correctly at startup.

Reproduction steps

  • Create a configuration file at ~/.config/mir_demo_server.live-config with high values for acceleration bias, e.g. :
pointer_acceleration=adaptive
pointer_acceleration_bias=1.0

touchpad_click_mode=clickfinger
touchpad_acceleration=adaptive
touchpad_acceleration_bias=1.0
  • Switch to a tty and run mir_demo_server
  • Test mouse and touchpad movement, movement should be normal
  • Switch to another tty, run touch ~/.config/mir_demo_server.live-config
  • Test mouse and touchpad movement again, movement should now be very fast

Relevant log output

Contributor guide

Research direction
Investigate the configuration loading logic to understand why pointer acceleration bias and touchpad acceleration bias are not applied at startup while keymap works. Check if these values are read but not applied until file modification triggers a reload.
Tech stack
cpp
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
C++Git
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65