use custom folder icon

icons/myicons/folder.svg

@@ -0,0 +1,17 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="512" height="512" viewBox="0 0 64 64">
+    <path d="
+	M5,50
+	L5,10
+	C5,5 10,5 10,5
+	L20,5
+	C23,5 25,9 25,9
+	C25,9,28,15 30,15
+	L55,15
+	C60,15 60.5,20 60,20
+	L60,50
+	C60,55 55,55 55,55
+	L10,55
+	C10,55 5,55 5,50"
+          style="fill:#ddd;stroke:black; stroke-width:4;"
+          transform="translate(0.5,0.5)"/>
+</svg>

src/plugins/filesbrowser/filesbrowserwidget.py

@@ -30,7 +30,7 @@ class FilesBrowserWidget(Tab):
         self._base_dir = QLineEdit(self._initialFolder())
         self._base_dir.textChanged.connect(self._base_dir_changed)
 
-        btn_select_base_dir = QPushButton(Icon("icons/ionicons/folder-open.svg"), "")
+        btn_select_base_dir = QPushButton(Icon("icons/myicons/folder.svg"), "")
         btn_select_base_dir.pressed.connect(self._select_base_dir)
 
         btn_base_dir_for_current_file = QPushButton(Icon("icons/myicons/target.svg"), "")