Horizontal mouse scroll switches tabs instead of being forwarded to the terminal application (GTK/Linux)

[folke]

Issue Description

Since upgrading to Ghostty 1.3.0, horizontal mouse scroll events (e.g. from a
mouse with a tilt wheel or two-finger horizontal trackpad scroll) switch tabs
instead of being forwarded to the foreground application (e.g. Neovim).

This appears to be caused by the two-finger swipe tab switching feature added
in PR #10575. On macOS, there is a macos-tab-swipe-navigation toggle to
disable this, but no equivalent exists for the GTK build.

Expected Behavior

Horizontal scroll events should be forwarded to the running terminal
application (like they were in 1.2.x), or there should be a configuration
option (e.g. gtk-tab-swipe-navigation) to disable tab switching via horizontal scroll on GTK.

Actual Behavior

Horizontal scroll events switch to the previous/next tab instead of being
passed through to the foreground application.

Reproduction Steps

1. Open Ghostty with multiple tabs
2. Run an application that handles horizontal scroll (e.g. Neovim with
   horizontal scroll mappings)
3. Perform a horizontal scroll (mouse tilt wheel or two-finger horizontal
   swipe)
4. Observe that tabs switch instead of the scroll being handled by the
   application

Ghostty Logs

No response

Ghostty Version

Ghostty 1.3.0-arch2.1

OS Version Information

Linux 6.19.7-1-cachyos (Arch/CachyOS)

(Linux only) Display Server

Wayland

(Linux only) Desktop Environment/Window Manager

Niri

Minimal Ghostty Configuration

gtk-tabs-location = bottom
keybind = super+shift+t=new_tab

Additional Relevant Configuration

No response

I acknowledge that:

• I have reviewed the FAQ and confirm that my issue is NOT among them.
• I have searched the Ghostty repository (both open and closed Discussions and Issues) and confirm this is not a duplicate of an existing issue or discussion.
• I have checked the "Preview" tab on all text fields to ensure that everything looks right, and have wrapped all configuration and code in code blocks with a group of three backticks (```) on separate lines.

[ErikReider]

I'm also experiencing this issue. There's also no config option for turning this off.