[v3] Normalize Windows paths on system Dialogs invocations

docs/src/content/docs/changelog.mdx

@@ -111,6 +111,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fixed initially-hidden menu items by [@IanVS](https://github.com/IanVS) in [#4116](https://github.com/wailsapp/wails/pull/4116)
 - Fixed assetFileServer not serving `.html` files when non-extension request when `[request]` doesn't exist but `[request].html` does
 - Fixed icon generation paths by [@robin-samuel](https://github.com/robin-samuel) in [#4125](https://github.com/wailsapp/wails/pull/4125)
+- Fixed Dialogs runtime function returning escaped paths on Windows by [TheGB0077](https://github.com/TheGB0077) in [#4188](https://github.com/wailsapp/wails/pull/4188)
 
 ### Changed
 

v3/pkg/application/dialogs_windows.go

@@ -247,7 +247,20 @@ func showCfdDialog(newDlg func() (cfd.Dialog, error), isMultiSelect bool) (any,
 	}()
 
 	if multi, _ := dlg.(cfd.OpenMultipleFilesDialog); multi != nil && isMultiSelect {
-		return multi.ShowAndGetResults()
+		paths, err := multi.ShowAndGetResults()
+		if err != nil {
+			return nil, err
+		}
+
+		for i, path := range paths {
+			paths[i] = filepath.Clean(path)
+		}
+		return paths, nil
+	}
+
+	path, err := dlg.ShowAndGetResult()
+	if err != nil {
+		return nil, err
 	}
-	return dlg.ShowAndGetResult()
+	return filepath.Clean(path), nil
 }

v3/pkg/application/dialogs_windows_test.go

@@ -0,0 +1,57 @@
+//go:build windows
+
+package application_test
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/matryer/is"
+)
+
+func TestCleanPath(t *testing.T) {
+	i := is.New(t)
+	tests := []struct {
+		name      string
+		inputPath string
+		expected  string
+	}{
+		{
+			name:      "path with double separators",
+			inputPath: `C:\\temp\\folder`,
+			expected:  `C:\temp\folder`,
+		},
+		{
+			name:      "path with forward slashes",
+			inputPath: `C://temp//folder`,
+			expected:  `C:\temp\folder`,
+		},
+		{
+			name:      "path with trailing separator",
+			inputPath: `C:\\temp\\folder\\`,
+			expected:  `C:\temp\folder`,
+		},
+		{
+			name:      "path with escaped tab character",
+			inputPath: `C:\\Users\\test\\tab.txt`,
+			expected:  `C:\Users\test\tab.txt`,
+		},
+		{
+			name:      "newline character",
+			inputPath: `C:\\Users\\test\\newline\\n.txt`,
+			expected:  `C:\Users\test\newline\n.txt`,
+		},
+		{
+			name:      "UNC path with multiple separators",
+			inputPath: `\\\\\\\\host\\share\\test.txt`,
+			expected:  `\\\\host\share\test.txt`,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cleaned := filepath.Clean(tt.inputPath)
+			i.Equal(cleaned, tt.expected)
+		})
+	}
+}