Steps to Reproduce:
1. Create a new site with a public page.
2. Enable local staging with page variation enabled.
3. Navigate to staging site page.
4. Create new site pages variation named as 'Summer'.
5. Go to Product Menu -> Site Builder -> Pages.
6. Assert 'Summer' is choosed as the current site pages variation.
7. Add a public page 'aaa' under 'Summer'.
8. Click on 'Main Variation' for choosing it as the current site pages variation.
Page 'aaa' shouldn't display under 'Main Variation'.
Page 'aaa' displays under 'Main Variation'. Page 'aaa' disappears after refresh the page.