Troubleshooting

Copied text doesn't reach my clipboard

tmux sends copied text to your terminal through OSC 52, and the terminal on your machine has to allow it. Check the setting for your terminal in tmux → Host terminal settings.

Also note how copying works in tmux: the text is copied when you release the mouse button. Pressing Cmd+C / Ctrl+Shift+C afterwards copies nothing.

I want to select text the usual way

Hold Shift (Ghostty) or Option (iTerm2) while dragging to use your terminal's own selection instead of tmux's. It selects whole lines across all panes.

Scrolling or copying behaves differently in one pane

In each pane, the mouse goes either to tmux or to the program running there:

• Programs that handle the mouse themselves (Claude Code, Neovim) scroll and select within their own interface.
• Everywhere else, tmux scrolls the pane's history and selects text within the pane.

To see which applies to a pane, press Ctrl+b, then :, and run:

display -d 0 "any=#{mouse_any_flag} btn=#{mouse_button_flag} std=#{mouse_standard_flag} sgr=#{mouse_sgr_flag} alt=#{alternate_on}"

The result stays in the status bar until you press a key. If any, btn or std is 1, the program in the pane is handling the mouse; if they are all 0, tmux is. Please include this line when reporting a problem.

Neovim shows no language server features

Language servers are downloaded by mason the first time Neovim starts in a new container, and this needs network access. Run :Mason to check the progress, and :checkhealth for other problems.

Still stuck?

See FAQ & Support.