diff --git a/src/Surface.zig b/src/Surface.zig
index 465d12122..707e69104 100644
--- a/src/Surface.zig
+++ b/src/Surface.zig
@@ -1283,8 +1283,11 @@ fn mouseReport(
     mods: input.Mods,
     pos: apprt.CursorPos,
 ) !void {
-    // TODO: posToViewport currently clamps to the surface boundary,
-    // do we want to not report mouse events at all outside the surface?
+    // The maximum pos values so we can determine if we're outside the window.
+    // If we're outside the window, we do not report mouse events.
+    const max_x: f32 = @floatFromInt(self.screen_size.width);
+    const max_y: f32 = @floatFromInt(self.screen_size.height);
+    if (pos.x < 0 or pos.y < 0 or pos.x > max_x or pos.y > max_y) return;
 
     // Depending on the event, we may do nothing at all.
     switch (self.io.terminal.flags.mouse_event) {
@@ -1444,6 +1447,9 @@ fn mouseReport(
         },
 
         .sgr_pixels => {
+            assert(pos.x >= 0);
+            assert(pos.y >= 0);
+
             // Final character to send in the CSI
             const final: u8 = if (action == .release) 'm' else 'M';
 
@@ -1452,8 +1458,8 @@ fn mouseReport(
             var data: termio.Message.WriteReq.Small.Array = undefined;
             const resp = try std.fmt.bufPrint(&data, "\x1B[<{d};{d};{d}{c}", .{
                 button_code,
-                pos.x,
-                pos.y,
+                @as(u32, @intFromFloat(@round(pos.x))),
+                @as(u32, @intFromFloat(@round(pos.y))),
                 final,
             });
 
diff --git a/src/terminal/stream.zig b/src/terminal/stream.zig
index 824d08ffa..3789d5611 100644
--- a/src/terminal/stream.zig
+++ b/src/terminal/stream.zig
@@ -300,16 +300,24 @@ pub fn Stream(comptime Handler: type) type {
                 ) else log.warn("unimplemented CSI callback: {}", .{action}),
 
                 // Scroll Up (SD)
-                'S' => if (@hasDecl(T, "scrollUp")) try self.handler.scrollUp(
-                    switch (action.params.len) {
-                        0 => 1,
-                        1 => action.params[0],
-                        else => {
-                            log.warn("invalid scroll up command: {}", .{action});
-                            return;
+
+                'S' => switch (action.intermediates.len) {
+                    0 => if (@hasDecl(T, "scrollUp")) try self.handler.scrollUp(
+                        switch (action.params.len) {
+                            0 => 1,
+                            1 => action.params[0],
+                            else => {
+                                log.warn("invalid scroll up command: {}", .{action});
+                                return;
+                            },
                         },
-                    },
-                ) else log.warn("unimplemented CSI callback: {}", .{action}),
+                    ) else log.warn("unimplemented CSI callback: {}", .{action}),
+
+                    else => log.warn(
+                        "ignoring unimplemented CSI S with intermediates: {s}",
+                        .{action.intermediates},
+                    ),
+                },
 
                 // Scroll Down (SD)
                 'T' => if (@hasDecl(T, "scrollDown")) try self.handler.scrollDown(