Options are lost on first save

Happened to me twice, on two different blogs.
Saving Reading options first time loses all checkboxes for plugin.

1. installed plugin
2. went to Reading
3. all checkboxes for plugin was checked by default
4. pressed Save, now page have no checkboxes checked for plugin
5. it’s not just-GUI issue: fitvids is not rendered for any page
6. checking them again and saving stores them fine from now on.

It may affect initial user experience.

https://www.ads-software.com/plugins/responsive-videos-fitvids/