Input methods (IBus/Fcitx5) don't work on COSMIC Wayland — shipped versions are too old

[ANDADAC]

Summary
Pop!_OS 24.04 ships IBus 1.5.29 and Fcitx5 5.1.7, neither of which works properly with COSMIC's Wayland compositor
(cosmic-comp). cosmic-comp implements zwp_input_method_v2, but:

• IBus 1.5.29 only supports zwp_input_method_v1 — it fails with "No input_method global" and crashes (SIGTRAP).
  Requires IBus ≥ 1.5.32.
• Fcitx5 5.1.7 has limited zwp_input_method_v2 support. Improved handling was added in Fcitx5 5.1.12.

This means CJK and other non-Latin input methods are completely broken out of the box on COSMIC.

Additional issue: pop-im-ibus.sh

/etc/profile.d/pop-im-ibus.sh hardcodes:

export GTK_IM_MODULE="ibus"
export QT_IM_MODULE="ibus"
export XMODIFIERS="@im=ibus"

This overrides im-config settings and prevents switching to Fcitx5. It also might conflict with IBus 1.5.32's Wayland
mode, which recommend GTK_IM_MODULE and QT_IM_MODULE to be unset.

Steps to reproduce

1. Fresh install Pop!_OS 24.04 with COSMIC desktop
2. Install ibus-hangul or fcitx5-hangul (or any CJK input method)
3. Configure with im-config and reboot
4. Attempt to type Korean/Chinese/Japanese/Vietnamese in Firefox

Expected: Input method works
Actual: No input method indicator appears, no language switching, no non-Latin input possible

Workaround

Manually install newer packages from Ubuntu 25.04 (Plucky):

For IBus:

Download and install IBus 1.5.32 from Ubuntu Plucky

sudo dpkg -i --force-depends libibus-1.0-5_1.5.32rc2-1_amd64.deb
ibus-data_1.5.32rc2-1_all.deb
gir1.2-ibus-1.0_1.5.32rc2-1_amd64.deb
python3-ibus-1.0_1.5.32rc2-1_all.deb
ibus_1.5.32~rc2-1_amd64.deb

For Fcitx5:

Download and install Fcitx5 5.1.12 from Ubuntu Plucky

sudo dpkg -i --force-depends libfcitx5config6_5.1.12-2_amd64.deb
libfcitx5core7_5.1.12-2_amd64.deb
libfcitx5utils2_5.1.12-2_amd64.deb
fcitx5-data_5.1.12-2_all.deb
fcitx5-modules_5.1.12-2_amd64.deb
fcitx5_5.1.12-2_amd64.deb

Additionally, /etc/profile.d/pop-im-ibus.sh must be removed.

Requested fix

1. Backport IBus ≥ 1.5.32 and/or Fcitx5 ≥ 5.1.12 to Pop!_OS 24.04
2. Remove or update pop-im-ibus.sh — it should either respect im-config or be removed entirely
3. Ideally, cosmic-session should auto-start the configured input method (see Please start IBus automatically if it is present so input methods work #110 in cosmic-session)

Environment

• Pop!_OS 24.04 LTS (released December 2025)
• COSMIC desktop (Epoch 1)
• cosmic-comp with zwp_input_method_v2 / zwp_text_input_v3
• IBus 1.5.29-2 (shipped) → 1.5.32 (required)
• Fcitx5 5.1.7 (shipped) → 5.1.12 (required)

Related issues

• Please start IBus automatically if it is present so input methods work #110 — auto-start IBus
• fcitx does not work pop#1445 — pop-im-ibus.sh breaks fcitx
• IME (Chinese, Japanese, etc.) input doesn't work in COSMIC apps cosmic-epoch#2174 — IME in native COSMIC apps (separate issue, needs iced 0.14 rebase)
• Add support for CJK input method editors libcosmic#578 — CJK IME support in libcosmic

[Cooljawty]

Just wanted to add a note on the workaround, I had to manually start ibus as well with ibus start --type wayland as mentioned in #110