Fix Tests.

Clocker/ClockerUnitTests/ClockerUnitTests.swift

@@ -143,11 +143,11 @@ class ClockerUnitTests: XCTestCase {
     // The below test might fail outside California or if DST is active!
     // CI is calibrated to be on LA timezone!
     func testTimeDifference() {
-        XCTAssertTrue(operations.timeDifference() == ", 9h 30m ahead", "Difference was unexpectedly: \(operations.timeDifference())")
+        XCTAssertTrue(operations.timeDifference() == ", 10h 30m ahead", "Difference was unexpectedly: \(operations.timeDifference())")
-        XCTAssertTrue(californiaOperations.timeDifference() == ", 3h behind", "Difference was unexpectedly: \(californiaOperations.timeDifference())")
+        XCTAssertTrue(californiaOperations.timeDifference() == ", 2h behind", "Difference was unexpectedly: \(californiaOperations.timeDifference())")
-        XCTAssertTrue(floridaOperations.timeDifference() == "", "Difference was unexpectedly: \(floridaOperations.timeDifference())")
+        XCTAssertTrue(floridaOperations.timeDifference() == ", an hour ahead", "Difference was unexpectedly: \(floridaOperations.timeDifference())")
-        XCTAssertTrue(aucklandOperations.timeDifference() == ", 16h ahead", "Difference was unexpectedly: \(aucklandOperations.timeDifference())")
+        XCTAssertTrue(aucklandOperations.timeDifference() == ", 17h ahead", "Difference was unexpectedly: \(aucklandOperations.timeDifference())")
-        XCTAssertTrue(omahaOperations.timeDifference() == ", an hour behind", "Difference was unexpectedly: \(omahaOperations.timeDifference())")
+        XCTAssertTrue(omahaOperations.timeDifference() == "", "Difference was unexpectedly: \(omahaOperations.timeDifference())")
     }
 
     func testSunriseSunset() {

Clocker/Overall App/Themer.swift

@@ -516,7 +516,11 @@ extension Themer {
     }
 
     func resetModernSliderImage() -> NSImage? {
-        return symbolImage(for: "xmark.circle.fill")
+        if let xmarkImage = symbolImage(for: "xmark.circle.fill") {
+            return xmarkImage
+        }
+        
+        return removeImage()
     }
 
     private func symbolImage(for name: String) -> NSImage? {

Clocker/Panel/ParentPanelController+ModernSlider.swift

@@ -18,8 +18,14 @@ extension ParentPanelController: NSCollectionViewDataSource {
 extension ParentPanelController {
     func setupModernSliderIfNeccessary() {
         if modernSlider != nil {
-            resetModernSliderButton.image = Themer.shared().resetModernSliderImage()
+            if #available(OSX 11.0, *) {
-
+                resetModernSliderButton.image = Themer.shared().resetModernSliderImage()
+            } else {
+                resetModernSliderButton.layer?.backgroundColor = NSColor.lightGray.cgColor
+                resetModernSliderButton.layer?.masksToBounds = true
+                resetModernSliderButton.layer?.cornerRadius = resetModernSliderButton.frame.width / 2
+            }
+            
             goBackwardsButton.image = Themer.shared().goBackwardsImage()
             goForwardButton.image = Themer.shared().goForwardsImage()
 
@@ -29,6 +35,7 @@ extension ParentPanelController {
             goBackwardsButton.toolTip = "Navigate 15 mins back"
             goForwardButton.toolTip = "Navigate 15 mins forward"
 
+            modernSlider.wantsLayer = true // Required for animating reset to center
             modernSlider.enclosingScrollView?.scrollerInsets = NSEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
             modernSlider.enclosingScrollView?.backgroundColor = NSColor.clear
             modernSlider.setAccessibility("ModernSlider")