Point 1 : 

Rename this button with "Terminer le sujet"

Point 2 : 

In a forum with a lot of threads (in order to see scroll bar) : go in the bottom of the list and delete a thread. 

=> Thread is correctly deleted but all threads are display in double (you can see the double by scrolling to the top). 

Point 3 :

• Select a thread,
• Click on it => pop up is opened
• Close the pop-up (either by clicking on the cross on the top left corner or by entrying echap key=
• Thread card is still displayed in grey :