Forward search by clicking on the blue pointer in the left margin of WinEdt's source box

I use WinEdt 10.3 and Sumatra. Until few days ago, I used to jump from a line of the source to the corresponding part of the PDF by clicking on this blue pointer, in the left margin, near from the line numbers:

Now, I can’t do this anymore. The direct search (jumping from the source to the corresponding part of the PDF) is still working when I use SHIFT + F8. But why that blue pointer does not work anymore for this purpose? How could I fix this?