This is the following of bug #1342.

@Alkarex you added the option disabled in order to prevent users to activate the mark as read feature before the script is loaded.
In my case, the option never disappears.

I'm wondering if the script is correctly loaded/launched.

Is it still an issue of caching, as I have (see #1342) ?
(the main.js script is cached, and removing the cache change nothing)

Thanks in advance for your help :)