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+
+
+
+### About the Converted Accessibility Tree
+
+For several applications like Firefox or Thunderbird, you should first enable
+
+```sh
+gsettings set org.gnome.desktop.interface toolkit-accessibility true
+```
+
+to see their accessibility tree.
+
+#### Example of AT
+
+An example of a node:
+
+```xml
+
+ 歡迎使用新的 Outlook.com 帳戶
+
+```
+
+An example of a tree:
+
+```xml
+
+
+ ...
+
+ ...
+
+```
+
+#### Useful attributes
+
+1. `name` - shows the name of application, title of window, or name of some
+ component
+2. `attr:class` - somewhat the same role as `class` in HTML
+3. `attr:id` - somewhat the same role as `id` in HTML
+4. `cp:screencoord` - absolute coordinator on the screen
+5. `cp:windowcoord` - relative coordinator in the window
+6. `cp:size` - the size
+
+Also several states like `st:enabled` and `st:visible` can be indicated. A full
+state list is available at
+.
+
+#### How to use it in evaluation
+
+See example `thunderbird/12086550-11c0-466b-b367-1d9e75b3910e.json` and
+function `check_accessibility_tree` in `metrics/general.py`. You can use CSS
+selector or XPath to reference a target nodes. You can also check its text
+contents.
+
+An example of a CSS selector:
+
+```css
+application[name=Thunderbird] page-tab-list[attr|id=\"tabmail-tabs\"]>page-tab[name=\"About Profiles\"]
+```
+
+This selector will select the page tab of profile manager in Thunderbird (if open).
+
+For usage of CSS selector: . For usage of XPath: .