Prevent page jumping when clicking buttons

package.json

@@ -1,6 +1,6 @@
 {
     "name": "minesweeper",
-    "version": "0.85.2",
+    "version": "0.85.3",
     "description": "Just Minesweeper!",
     "author": "Florine W. Dekker",
     "browser": "dist/bundle.js",

src/main/js/Game.ts

@@ -107,6 +107,7 @@ export class Game {
                     +this.minesInput.value,
                     this.solvableInput.checked
                 );
+                this.customDifficultyOverlay.close();
             }
         });
 
@@ -120,12 +121,22 @@ export class Game {
         // New game form
         $("#new-game").addEventListener(
             "click",
-            () =>
+            (event: MouseEvent) => {
-                this.initNewField(this.field?.width, this.field?.height, this.field?.mineCount, this.field?.isSolvable)
+                event.preventDefault();
+
+                this.initNewField(this.field?.width, this.field?.height, this.field?.mineCount, this.field?.isSolvable);
+            }
         );
 
         // Restart
-        $("#restart").addEventListener("click", () => this.field?.undo());  // Undoes all
+        $("#restart").addEventListener(
+            "click",
+            (event: MouseEvent) => {
+                event.preventDefault();
+
+                this.field?.undo();  // Undoes all
+            }
+        );
 
         // Seed
         const seedInput = $("#seed");
@@ -150,17 +161,33 @@ export class Game {
 
         // Undo
         this.undo = $("#undo");
-        this.undo.addEventListener("click", () => this.field?.undo(1));
+        this.undo.addEventListener(
+            "click",
+            (event: MouseEvent) => {
+                event.preventDefault();
+
+                return this.field?.undo(1);
+            }
+        );
 
         // Redo
         this.redo = $("#redo");
-        this.redo.addEventListener("click", () => this.field?.redo(1));
+        this.redo.addEventListener(
+            "click",
+            (event: MouseEvent) => {
+                event.preventDefault();
+
+                return this.field?.redo(1);
+            }
+        );
 
         // Hint
         this.hint = $("#hint");
         this.hint.addEventListener(
             "click",
-            () => {
+            (event: MouseEvent) => {
+                event.preventDefault();
+
                 if (this.field != null) {
                     this.statistics.hintsRequested++;
                     this.display.hintSquare = Solver.getHint(this.field);
@@ -172,7 +199,9 @@ export class Game {
         this.solve = $("#solve");
         this.solve.addEventListener(
             "click",
-            () => {
+            (event: MouseEvent) => {
+                event.preventDefault();
+
                 if (this.field != null) {
                     this.statistics.solverUsages++;
                     Solver.solve(this.field);