Select page export selector is not working properly

Reproduction steps:
1. On a fresh wiki, create 3 pages and edit the homepage
2. Go to Administration > Content > Export
3. By default "Created and modified pages" is selected
4. Select "Created pages", and verify which pages are selected
5. Select back "Created and modified pages" and verify which pages are selected
6. Click on "None" to deselect everything
7. Select back "Created pages" and verify which pages are selected

Expected result:

• Since the selector is supposed to automatically select pages, we should see each time we select back an option the proper pages automatically selected

Obtained result:

• Apparently each choice definitely overrides all future choices: selections are wrong for steps 5 and 7.

Note that I only tested this on firefox.