No mouse drag end event when dragging mouse out of the window

[anhpt379]

Describe the bug
I'm on macOS Sonoma 14.3.1. When using tmux (version 3.4), the MouseDragEnd1Pane event doesn't get triggered when I drag the mouse out of the current window. I've tried with the default macOS Terminal app, and WezTerm, they don't have this issue.

To Reproduce
Steps to reproduce the behavior:

1. Copy this config to /tmp/tmux.conf:

set-option -g mouse on
set-option -g mode-keys vi
bind-key -T copy-mode-vi MouseDragEnd1Pane display-message "Drag ended"

2. Launch tmux with the config file above: tmux -f /tmp/tmux.conf.
3. Press the left mouse button in the middle of a text line in the window.
4. Hold and drag the mouse to the left, outside of the current window.
5. Release the left mouse button.
6. No Drag ended doesn't show up, meaning the mouse drag end event doesn't fire.

Environment details

kitty 0.33.1 (a5fea33757) created by Kovid Goyal
Darwin L2HHKL97RH 23.3.0 Darwin Kernel Version 23.3.0: Wed Dec 20 21:30:44 PST 2023; root:xnu-10002.81.5~7/RELEASE_ARM64_T6000 arm64
ProductName:		macOS ProductVersion:		14.3.1 BuildVersion:		23D60
Frozen: True
Paths:
  kitty: /Users/panh/Applications/kitty.app/Contents/MacOS/kitty
  base dir: /Users/panh/Applications/kitty.app/Contents/Resources/kitty
  extensions dir: /Users/panh/Applications/kitty.app/Contents/Resources/Python/lib/kitty-extensions
  system shell: /bin/bash

Config options different from defaults:
Removed shortcuts:
	cmd+, →  edit_config_file
	cmd+enter →  new_window
	cmd+h →  hide_macos_app
	cmd+k →  clear_terminal to_cursor active
	cmd+m →  minimize_macos_window
	cmd+n →  new_os_window
	cmd+q →  quit
	cmd+t →  new_tab
	cmd+w →  close_tab
	ctrl+cmd+, →  load_config_file
	ctrl+cmd+f →  toggle_fullscreen
	opt+cmd+h →  hide_macos_other_apps
	opt+cmd+r →  clear_terminal reset active
	opt+cmd+s →  toggle_macos_secure_keyboard_entry
	shift+cmd+/ →  open_url https://sw.kovidgoyal.net/kitty/
	shift+cmd+[ →  previous_tab
	shift+cmd+] →  next_tab
	shift+cmd+d →  close_window
	shift+cmd+w →  close_os_window

Important environment variables seen by the kitty process:
	PATH                                /usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/Applications/Privileges.app/Contents/Resources:/usr/local/munki:/Users/panh/Applications/kitty.app/Contents/MacOS
	LANG                                en_US.UTF-8
	SHELL                               /bin/bash
	DISPLAY                             /private/tmp/com.apple.launchd.gxTONFhPQD/org.xquartz:0
	USER                                panh

Additional context
It sort of works when using the default font size, and when the window is in full screen mode: dragging the mouse to the left edge of the screen and release, the message Drag ended shows up. But when switching to a different font size it stops working.

[kovidgoyal]

Please come up witha reproducer not involving tmux. Simply run

kitty kitten mouse-demo

to see what mouse events are delivered to a program running inside
kitty. And run kitty with --debug-input to see what events are delivered
to kitty itself.

[anhpt379]

It happens when something grabs the mouse (like neovim with set mouse=a, or tmux with set -g mouse on, or less --MOUSE).

Here's how to reproduce it:

1. Run kitty --debug-input.
2. Run less --MOUSE /path/to/a/file on the newly created window (I'm using less version 643).
3. Start dragging, with the starting point in the window.
4. Drag the mouse out of the window, and release.

When releasing the mouse in the window, the debug log shows 2 events:

Move x: 116.0 y: 282.1 grabbed: 1
Move x: 116.4 y: 282.1 grabbed: 1
Move x: 116.9 y: 282.1 grabbed: 1
Release mouse_button: 0 mods: none grabbed: 1
on_mouse_input: release button: left mods: none grabbed: 1 handled_in_kitty: 0
Move x: 117.9 y: 282.1 grabbed: 1
Move x: 118.3 y: 282.1 grabbed: 1

When releasing the mouse outside of the window, the debug log doesn't show the on_mouse_input line:

Move x: -104.3 y: 105.2
Move x: -104.6 y: 105.0
Release mouse_button: 0 mods: none
Move x: -104.1 y: 104.8
Move x: -101.7 y: 106.0

When running less without --MOUSE and trying to release the mouse both inside & outside the window, the debug log shows only something like this (with no on_mouse_input line):

Move x: 32.7 y: 101.6 handled as drag move
Move x: 32.2 y: 101.6 handled as drag move
Release mouse_button: 0 mods: none handled as drag end
Move x: 31.2 y: 101.6 grabbed: 0
Move x: 31.6 y: 101.6 grabbed: 0

[kovidgoyal]

kitten mouse-demo grabs the mouse. It doesn't reproduce for me in either
X11 or macOS (via VNC) with kitten mouse-demo. Haven't tried with less
but I dont see why that would make a difference. Are you saying it
doesn't reproduce for you with mouse-demo but does with less? Or if it
reproduces with both is there something unusual about your system? I
will try it on macOS without VNC when I next have access to my mac.

[anhpt379]

For kitty kitten mouse-demo, when I drag & release the mouse in the window, the Type always stays at move. When I release the mouse outside of the window, the Type switches to release. I don't know what that means.

For less or nvim with mouse mode on, they don't provide any visual indicator for the issue. The only difference I saw was the on_mouse_input line in the kitty --debug-input log.

[kovidgoyal]

type switching to release means the release event is being reported,
correctly. Make sure your mouse doesnt move while releasing if you are
not seeing the release event in mouse-demo. I'll look at it with less
when I have a moment.

[anhpt379]

I'm sure that my mouse doesn't move when I release the button. The type in mouse-demo only switches to release when I release the mouse outside the window. When inside, the type always stays at move both when I drag & when I release the mouse button.

[kovidgoyal]

On Thu, Mar 21, 2024 at 07:50:38AM -0700, Anh Pham wrote: I'm sure that my mouse doesn't move when I release the button. The type in mouse-demo only switches to `release` when I release the mouse outside the window. When inside, the type always stays at `move` both when I drag & when I release the mouse button.

That does not reproduce for me.

[anhpt379]

I made a recording for it:
https://github.com/kovidgoyal/kitty/assets/222319/3f13166a-ad6d-4120-8c7c-4e7ec64f7035

Can you suggest what else for me to try?

[kovidgoyal]

You dont need to try anything, your original issue is fixed already.

[anhpt379]

ah, sorry I didn't notice the commit. Thank you for being so responsive :)