Mouse cursor disappears after full screen video

[a-b]

Steps to reproduce

Not always but quite often:

1. On macOS 15.7, open Telegram and play the video in full screen.
2. Sometimes, the cursor disappears system-wide. It still works, just invisible.
3. Blindly move the cursor outside the Telegram window
4. Click outside, and it reappears.

Expected behaviour

The cursor is visible when full-screen playback is over.

Actual behaviour

It is hidden until I press outside the Telegram window.

Operating system

macOS 15.7

Version of Telegram Desktop

12.1.276137 Stable

Installation source

Static binary from official website

Crash ID

No response

Logs

[zhiln]

same here

[SnoElement]

We investigated this further and found the root cause. Here are reliable reproduction steps and the technical explanation.

Reproduction steps (most reliable)

1. Open Telegram and navigate to a chat with a video attachment.
2. Click the video to open it in the media viewer.
3. Enter full screen (double-click the video or use the full-screen button).
4. Let the mouse sit still for ~1 second — the playback controls fade out and the cursor disappears.
5. Now press Escape to close the viewer (or navigate to another item with the arrow keys, then close).
6. Result: the cursor remains invisible system-wide. It only comes back after clicking outside Telegram or switching focus.

A second, slightly harder to trigger variant: while in full screen, click the video once (pauses/plays) without moving the mouse. The controls-hide path and the idle-timer path can both fire NSCursor.hide(), after which a single NSCursor.unhide() on close is not enough.

Root cause

macOS cursor visibility is reference-counted — NSCursor.hide() and NSCursor.unhide() must be perfectly balanced. There are two independent places in SVideoController that call NSCursor.hide():

1. Idle timer (updateIdleTimer): hides the cursor after 1 s of inactivity.
2. Fullscreen mouse-event path (updateControlVisibility(true)): called from leftMouseDown/leftMouseUp, independently also calls NSCursor.hide() when the controls are dismissed.

viewDidDisappear only calls NSCursor.unhide() once, leaving the system count unbalanced when both paths fire.

Additionally, GalleryViewer.close(animated: false) (the Escape/snap-close path) calls window.orderOut() directly without going through item.disappear(), so viewDidDisappear — and its NSCursor.unhide() — never ran at all.

Fix

PR: #1357

• SVideoController: added isCursorHidden: Bool to track state. Every NSCursor.hide() is guarded by !isCursorHidden and every NSCursor.unhide() by isCursorHidden, guaranteeing exactly one balanced pair per lifecycle.
• GalleryViewer.close(animated:): call selectedItem?.disappear() before window.orderOut() in the non-animated path so viewDidDisappear always executes.