Label no longer clickable in Vaadin 8?

I am using TreeTable to display values that the user can select. Each node is made up of an HorizontalLayout with a Label. Under Vaadin 7 you can click anywhere on the HorizontalLayout, including on the Label, and the line will be selected. Under Vaadin 8 you have to click outside the Label area (either just to the left or to the right of the Label) to select; if you click on the Label text, nothing occurs.
Could someone explain or suggest a solution or a workaround? Thanks!

I now use a button styled as a Label so the functionnality is back, but the change in behaviour is strange...