#cmux 0.64.20: Native AppKit Sidebar, Browser Design Mode, TUI Mouse Forwarding

July 19, 2026

Native AppKit Sidebar. The workspace sidebar is rebuilt on native AppKit rows and is now on by default: faster scrolling in large workspace lists, precise hover and selection, and full fidelity with your sidebar settings.

Browser Design Mode. Visually edit pages inside the browser pane, annotate elements, and hand the annotated changes straight to an agent to implement.

Mouse Input for TUI Apps. cmux now forwards mouse input to TUI applications running in the terminal, so tools that own the pointer respond to clicks, drags, and scrolls as expected.

Stability and Performance. Codex YOLO mode and Pi sessions survive restore, typing latency from title churn is fixed, sidebar scroll livelocks and popover resize crashes are gone, and remote ssh-tmux panes size and focus correctly.

Added

Native AppKit workspace sidebar, now on by default: faster scrolling, precise hover and selection, and full settings fidelity (#8270, #8433, #8366, #8390, #8415, #8432, #8450) -- thanks @azooz2003-bit!
Browser Design Mode: visually edit pages in the browser pane, annotate elements, and hand the changes to an agent (#8034, #8393)
Forward mouse input to TUI applications running in the terminal (#7759)
Surface and workspace reorder shortcuts (#8080)
Session content width setting, and the previous width ceiling is removed (#8222, #8338)
Attach images to todos (#8117) -- thanks @azooz2003-bit!
OpenCode: Fork Conversation from the tab context menu (#8140)
Resize browser pane viewports (#8072)
CLI: cmux ssh accepts an initial remote command (#8439)
Share native SSH connections per host (#8308)
Notify on fatal Codex turn errors (#8170)
iOS (beta): files gallery with folders, previews, and a streaming viewer (#8287) -- thanks @azooz2003-bit!

Changed

Update pill installs are causal and fail visibly instead of silently (#8375)
The sidebar scroll indicator shows only while scrolling (#7976)
Group cmux TUI context menu actions (#8225)
Reap the persistent SSH daemon when its workspace closes (#8073)
Tighten terminal textbox top spacing (#8322)

Fixed

Preserve Codex YOLO mode across session restore and resume repair (#8133, #8045)
Preserve Pi sessions after workspace restore (#7628) -- thanks @silouanwright!
Fix Pi and OMP fork actions in tab context menus (#8173)
Fix Cmd-click for soft-wrapped URLs (#8110)
Fix typing latency from title churn (#8084, #8155)
Fix a sidebar scroll layout livelock (#8211) and sidebar GitHub polling regressions (#8226, #8190)
Replace per-row sidebar hover reconcilers with a single pointer owner (#8067) -- thanks @azooz2003-bit!
Fix Dock split rendering and shortcut routing (#8142)
Fix tmux mirror pane sizing and divider drag synchronization (#7996) -- thanks @ejc3!
Fix new-surface targeting and tab rename for remote tmux panes (#8403, #8404); fix ssh-tmux lifecycle and window-focus routing (#8405, #8402)
SSH: clear the auth marker after successful startup (#8410); fix the Ghostty SSH wrapper path in embedded app bundles (#8109)
Coalesce terminal resizes during split-divider drags (#8240)
Fix interaction paths in capped session panes (#8250)
Fix automatic terminal top inset (#8168)
Fix Files panel contrast across appearances (#8290)
Fix inconsistent table border thickness (#8193)
Fix a visible popover resize crash (#8115) -- thanks @azooz2003-bit! -- and update-popover resize reentrancy (#8195)
Bound overflowing confirmation dialog content (#8296)
Fix Settings shortcut display for legacy overrides (#8091)
Browser: fix Space key handling (#8079), numeric eval formatting (#8077), and wedged automation recovery (#8094)
iOS (beta): authenticated Iroh transport with cold-start retries and stale-session recovery (#7908, #8181, #8286, #8196, #8424) -- thanks @azooz2003-bit!
iOS (beta): match terminal themes across chrome and live reloads (#7919)
iOS (beta): smooth workspace-list scrolling with exact row heights (#8186); fix reconnect and build isolation (#8299) -- thanks @azooz2003-bit!

Contributors