macOS: save frame only if the window is visible

macos/Sources/Features/Terminal/TerminalController.swift

@@ -1171,27 +1171,21 @@ class TerminalController: BaseTerminalController, TabGroupCloseCoordinator.Contr
         self.fixTabBar()
 
         // Whenever we move save our last position for the next start.
-        if let window {
-            LastWindowPosition.shared.save(window)
-        }
+        LastWindowPosition.shared.save(window)
     }
 
     override func windowDidResize(_ notification: Notification) {
         super.windowDidResize(notification)
 
         // Whenever we resize save our last position and size for the next start.
-        if let window {
-            LastWindowPosition.shared.save(window)
-        }
+        LastWindowPosition.shared.save(window)
     }
 
     func windowDidBecomeMain(_ notification: Notification) {
         // Whenever we get focused, use that as our last window position for
         // restart. This differs from Terminal.app but matches iTerm2 behavior
         // and I think its sensible.
-        if let window {
-            LastWindowPosition.shared.save(window)
-        }
+        LastWindowPosition.shared.save(window)
 
         // Remember our last main
         Self.lastMain = self

macos/Sources/Helpers/LastWindowPosition.swift

@@ -6,10 +6,17 @@ class LastWindowPosition {
 
     private let positionKey = "NSWindowLastPosition"
 
-    func save(_ window: NSWindow) {
+    @discardableResult
+    func save(_ window: NSWindow?) -> Bool {
+        // We should only save the frame if the window is visible.
+        // This avoids overriding the previously saved one
+        // with the wrong one when window decorations change while creating,
+        // e.g. adding a toolbar affects the window's frame.
+        guard let window, window.isVisible else { return false }
         let frame = window.frame
         let rect = [frame.origin.x, frame.origin.y, frame.size.width, frame.size.height]
         UserDefaults.standard.set(rect, forKey: positionKey)
+        return true
     }
 
     func restore(_ window: NSWindow) -> Bool {