Don't steal focus on mouse events that are within 1 px

src/apprt/gtk/Surface.zig

@@ -1426,12 +1426,15 @@ fn gtkMouseMotion(
         .y = @floatCast(scaled.y),
     };
 
+    const is_cursor_still = @abs(self.cursor_pos.x - pos.x) < 1 and
+        @abs(self.cursor_pos.y - pos.y) < 1;
+
     // Our pos changed, update
     self.cursor_pos = pos;
 
     // If we don't have focus, and we want it, grab it.
     const gl_widget = @as(*c.GtkWidget, @ptrCast(self.gl_area));
-    if (c.gtk_widget_has_focus(gl_widget) == 0 and self.app.config.@"focus-follows-mouse") {
+    if (!is_cursor_still and c.gtk_widget_has_focus(gl_widget) == 0 and self.app.config.@"focus-follows-mouse") {
         self.grabFocus();
     }