feat: support voiceover + "speak items under the cursor" (closes #1070)

src/logic/Windows.swift

@@ -72,6 +72,15 @@ class Windows {
         let focusedView = ThumbnailsView.recycledViews[focusedWindowIndex]
         focusedView.highlight(true)
         App.app.thumbnailsPanel.thumbnailsView.scrollView.contentView.scrollToVisible(focusedView.frame)
+        voiceOverFocusedWindow()
+    }
+
+    static func voiceOverFocusedWindow() {
+        guard App.app.appIsBeingUsed && App.app.thumbnailsPanel.isKeyWindow else { return }
+        let window = ThumbnailsView.recycledViews[focusedWindowIndex]
+        if window.window_ != nil && window.window != nil {
+            App.app.thumbnailsPanel.makeFirstResponder(window)
+        }
     }
 
     static func focusedWindow() -> Window? {

src/ui/App.swift

@@ -217,6 +217,7 @@ class App: AppCenterApplication, NSApplicationDelegate {
         thumbnailsPanel.thumbnailsView.updateItemsAndLayout(currentScreen)
         guard appIsBeingUsed else { return }
         thumbnailsPanel.setContentSize(thumbnailsPanel.thumbnailsView.frame.size)
+        Windows.voiceOverFocusedWindow() // at this point ThumbnailViews are assigned to the window, and ready
         thumbnailsPanel.display()
         guard appIsBeingUsed else { return }
         currentScreen.repositionPanel(thumbnailsPanel, .appleCentered)

src/ui/main-window/ThumbnailView.swift

@@ -22,6 +22,12 @@ class ThumbnailView: NSStackView {
     var isShowingWindowControls = false
     var windowlessIcon = FontIcon(.newWindow)
 
+    // for VoiceOver cursor
+    override var canBecomeKeyView: Bool { true }
+    override var acceptsFirstResponder: Bool { true }
+
+    override func isAccessibilityElement() -> Bool { true }
+
     convenience init() {
         self.init(frame: .zero)
         setupView()
@@ -44,6 +50,7 @@ class ThumbnailView: NSStackView {
         addWindowControls()
         addDockLabelIcon()
         thumbnail.addSubview(windowlessIcon, positioned: .above, relativeTo: nil)
+        setAccessibilityChildren([])
     }
 
     private func addDockLabelIcon() {
@@ -109,6 +116,7 @@ class ThumbnailView: NSStackView {
             let thumbnailSize = NSSize(width: thumbnailWidth.rounded(), height: thumbnailHeight.rounded())
             thumbnail.image?.size = thumbnailSize
             thumbnail.frame.size = thumbnailSize
+            thumbnail.setAccessibilityLabel(element.title)
         }
         assignIfDifferent(&spacing, Preferences.hideThumbnails ? 0 : Preferences.intraCellPadding)
         assignIfDifferent(&hStackView.spacing, Preferences.fontHeight == 0 ? 0 : Preferences.intraCellPadding)
@@ -117,12 +125,14 @@ class ThumbnailView: NSStackView {
             let appIconSize = NSSize(width: Preferences.iconSize, height: Preferences.iconSize)
             appIcon.image?.size = appIconSize
             appIcon.frame.size = appIconSize
+            appIcon.setAccessibilityTitle(element.application.runningApplication.localizedName)
         }
         let labelChanged = label.string != element.title
         if labelChanged {
             label.string = element.title
             // workaround: setting string on NSTextView changes the font (most likely a Cocoa bug)
             label.font = Preferences.font
+            setAccessibilityTitle(element.title)
         }
         assignIfDifferent(&hiddenIcon.isHidden, !element.isHidden || Preferences.hideStatusIcons)
         assignIfDifferent(&fullscreenIcon.isHidden, !element.isFullscreen || Preferences.hideStatusIcons)
@@ -169,8 +179,10 @@ class ThumbnailView: NSStackView {
             let view = dockLabelIcon.subviews[1] as! ThumbnailFontIconView
             if dockLabel > 30 {
                 view.setFilledStar()
+                view.setAccessibilityLabel("Red badge with star")
             } else {
                 view.setNumber(dockLabel, true)
+                view.setAccessibilityLabel("Red badge with number \(dockLabel)")
             }
             dockLabelIcon.setFrameOrigin(NSPoint(x: appIcon.frame.maxX - dockLabelIcon.fittingSize.width - 1, y: appIcon.frame.maxY - dockLabelIcon.fittingSize.height + 4))
         }

src/ui/main-window/ThumbnailsPanel.swift

@@ -14,8 +14,6 @@ class ThumbnailsPanel: NSPanel, NSWindowDelegate {
         titleVisibility = .hidden
         backgroundColor = .clear
         contentView!.addSubview(thumbnailsView)
-        preservesContentDuringLiveResize = false
-        disableSnapshotRestoration()
         // triggering AltTab before or during Space transition animation brings the window on the Space post-transition
         collectionBehavior = .canJoinAllSpaces
         // 2nd highest level possible; this allows the app to go on top of context menus
@@ -23,6 +21,8 @@ class ThumbnailsPanel: NSPanel, NSWindowDelegate {
         level = .popUpMenu
         // helps filter out this window from the thumbnails
         setAccessibilitySubrole(.unknown)
+        // for VoiceOver
+        setAccessibilityLabel(App.name)
     }
 
     func windowDidResignKey(_ notification: Notification) {

src/ui/main-window/WindowControlView.swift

@@ -14,6 +14,8 @@ class WindowControlView: NSImageView {
         originalImage = image
         hoveredImage = image.tinted(.init(white: 0, alpha: 0.25))
         hovered(false)
+        setAccessibilityLabel(imageName)
+        setAccessibilityRole(.button)
     }
 
     func hovered(_ isHovered: Bool) {