"Unread" topic after sending post for this topic

Preconditions

1. Registered user Loged In to JCommune
2. Go to any branch with a big number of posts in ONE topic (more 15)
3. This topic MUST be marked as "UnRead"

Steps to reproduce

1. Click on the topic link
2. Create post with some text data or any valid data
3. Close JCommune tab
4. Open JCommune again
5. Go to the branch where post was created

Actual result
The topic is marked as "Unread"

Expected result
The topic is marked as "Read"