fix: rare crash at launch

src/logic/events/MouseEvents.swift

@@ -10,18 +10,14 @@ class MouseEvents {
         observe_()
     }
 
-    static func disable() {
-        shouldBeEnabled = false
-        CGEvent.tapEnable(tap: eventTap, enable: false)
-    }
-
-    static func enable() {
-        shouldBeEnabled = true
-        CGEvent.tapEnable(tap: eventTap, enable: true)
+    static func toggle(_ enabled: Bool) {
+        shouldBeEnabled = enabled
+        if let eventTap = eventTap {
+            CGEvent.tapEnable(tap: eventTap, enable: enabled)
+        }
     }
 }
 
-
 private func observe_() {
     let eventMask = [CGEventType.leftMouseDown, CGEventType.leftMouseUp].reduce(CGEventMask(0), { $0 | (1 << $1.rawValue) })
     // CGEvent.tapCreate returns null if ensureAccessibilityCheckboxIsChecked() didn't pass
@@ -32,7 +28,7 @@ private func observe_() {
         eventsOfInterest: eventMask,
         callback: mouseHandler,
         userInfo: nil)
-    MouseEvents.disable()
+    MouseEvents.toggle(false)
     let runLoopSource = CFMachPortCreateRunLoopSource(kCFAllocatorDefault, eventTap, 0)
     CFRunLoopAddSource(BackgroundWork.mouseEventsThread.runLoop, runLoopSource, .commonModes)
 }

src/ui/App.swift

@@ -135,7 +135,7 @@ class App: AppCenterApplication, NSApplicationDelegate {
         debugPrint("hideUi")
         appIsBeingUsed = false
         isFirstSummon = true
-        MouseEvents.disable()
+        MouseEvents.toggle(false)
         thumbnailsPanel.orderOut(nil)
     }
 

src/ui/main-window/ThumbnailsPanel.swift

@@ -27,7 +27,7 @@ class ThumbnailsPanel: NSPanel {
 
     func show() {
         orderFrontRegardless()
-        MouseEvents.enable()
+        MouseEvents.toggle(true)
         thumbnailsView.scrollView.flashScrollers()
     }