Wrong size for the menu when showing the duplicates (Chrome)

Using Google Chrome, when the duplicates section is shown, the size of the menu is wrong: it takes the whole page whereas the tables in the duplicates section need more space than the actual width available on mobile.

The following CSS seems to fix it but needs some tests.

.main > div > div.row:last-child {
    overflow: hidden;
}

Before I make a MR, could some of you test it please ?