System and IINA version:

• macOS 13.1
• IINA 1.3.1 (latest develop: da1e06c)

I've been frustrated by this issue for quite a while now, and although I couldn't find anything via a quick search, I'm pretty sure I've come across at least a couple user reports that noted there was "no way to close the side panel" or that clicking to close didn't work reliably. I finally committed a big chunk of time to tracking it down, and I think I've found the culprit.

To get a better view of how clicks were being registered, I placed these logging statements at the start of these methods in MainWindowController:

  override func mouseDown(with event: NSEvent) {
    Logger.log("MainWindow mouseDown \(event.locationInWindow)", level: .verbose, subsystem: player.subsystem)
...

  override func mouseDragged(with event: NSEvent) {
    Logger.log("MainWindow mouseDrag \(event.locationInWindow)", level: .verbose, subsystem: player.subsystem)
...

  override func mouseUp(with event: NSEvent) {
  Logger.log("MainWindow mouseUp! isDragging: \(isDragging), isResizingSidebar: \(isResizingSidebar), clickCount: \(event.clickCount)", level: .verbose, subsystem: player.subsystem)
...

When I ran IINA with my test logging, I saw messages in the log like these:

01:06:22.638 [player0][v] MainWindow: mouseDown: (247.8671875, 417.46875)
01:06:22.640 [player0][v] MainWindow: mouseDragged: (247.8671875, 417.5859375)
01:06:22.767 [player0][v] MainWindow mouseUp! isDragging: true, isResizingSidebar: false, clickCount=1

This declared my tap was a "drag" (and thus not a click) even though my click lasted for 127ms and the drag distance was only 0.1pt in screen coordinates!

I should point out that I'm using the trackpad on a 16" MacBook Pro M1 Pro. Unlike most developers, I never use a mouse. (It's one of the main reasons I use Macs instead of other operating systems: multi-touch on on Linux/Windows has been almost unusable). And I happen to wear a glove size XL - I've got large hands and fingers. So I can see how this problem may not be noticeable for a mouse user, or someone who has smaller fingers. But for me, Apple's trackpad is so sensitive that it will send a "drag" notification even if my finger does a tiny rolling motion during a tap, or if my motion isn't straight down and up again. This is an unreasonable amount of precision to expect, and it doesn't align with other apps' behavior.

Expected behavior:

If the user does what a reasonable person considers to be a "tap", IINA should respond to it as a tap. It should only think the user is dragging once they drag some very small minimum distance, or hold it down longer than some reasonable time threshold, or both.

Actual behavior:

Sometimes users' taps or clicks are basically ignored because IINA incorrectly concluded that they wanted to quickly move the window by a single pixel or less.

Steps to reproduce:

See above.

How often does this happen?

When trying to close a side panel by tapping the video, there's about a 50-75% chance that my first tap will fail and a second attempt is needed. Probably the frequency varies widely between different users based on their usage patterns, and maybe trackpad users are more affected than mouse users.