Store the preferred width of the left tab bar separately from its actual width, which is constrained by the width of the window. The preferred width is set by a manual drag and is persisted in user defaults. When the window is wide enough to accommodate the preferred width, the tab bar will grow up to but not beyond that size. Issue 5833

Call refresh after changing font size to avoid doing a double redraw at two different scroll positions. Issue 5836

If a window has a nil screen, it would get resized to 0x0. Just accept the proposed size in this case. Issue 5641

Make it possible to open the tmux dashboard if there are no windows opened and the tmux gateway is buried. Issue 5835

Fix the origin of a new window that's created when you drag a tab out of the tab bar and drop it on nothing. What happened was the window got resized after adding the first tab to it and its originally (approximately) correct origin changed. The location is much closer to correct now and has been tested for all tab bar locations. Issue 5832.

Avoid filesystem access to network mounts by semantic history. fileURLWithPath: and standardizedURL would both perform I/O. Issue 5740.

When you drag a tab from the tabbar into a split pane, that causes removeTab: to be called. It tries to create a restorable session to undo closure, but because no sessions actually get closed in this operation we create an empty shell of a restorable session. When it's restored, you get a zombie tab with no view. This commit ignores such operations and declines to push a restorable session on the stack. Issue 5785.

Fix a bug where the root splitter's isvertical did not change if necessary when restoring a split pane. To repro:

1. Split vertically
2. Split horizontally

+---+---+
|   | B |
| A +---+
|   | C |
+---+---+

3. Close A
4. Undo close of A

The root splitter was  not reset to vertical after undo, so there were two horizontal splits.

It upsets High Sierra. 

Issue 5811

Add an advanced pref to control which pane is focused on split pane when using focus follows mouse. Issue 5780

Restore the find progress bar. When you do a search, perform the first chunk of work immediately. Make the timer run regardless of runloop mode so you can hold down cmd-shift-G and search fast.

Clean up how find-next works and fix a bug where the search results could be nonmonotonic and include duplicates because of tail find. Issue 5797.

Fix a bug where non-animated hotkey windows did not follow the cursor from screen to screen. Issue 5786.

Add a date format to the helpful string parser to handle dates like "Tue, 16 May 2017 06:32:33 UTC".

Add a few new notifications to the API server for session terminated (i.e., removed from UI) and layout changed. Update the python library to keep its window hierarchy in synch with the truth.

Fix apparent direction of animation of activity indicator in the tabbar

Fix leak of password manager sheet window. Also add advanced pref to disable its animation. Issue 5794

issue 5795

Fix a bug when two websocket frames are read at once. The offset was not reset so the second one got dropped.

Add NewSessionSubscription.

Add idle observers. Before entering a cond-wait on the main thread let each idle observer run. A notification handler is registered as an idle observer to handle incoming notifications.

Improve debug logging.