[orca-list] Orca skips content on a web page

[Alex ARNAUD <alexarnaud hypra fr>]

Hello,

Environment:
- Orca master
- Debian 9 "Stretch"
- Firefox 68

Steps to reproduce:
1) Open this page "https://www.piloter.org/strategie/strategie-drucker.htm";
2) Move to the  line beginning by "ouvrir pour autant de nouvelles 
perspectives de marché."
3) Press down arrow

Result:
Orca switch on the header "3) Trouver et occuper une niche "

Expected result:
I assume Orca should switch on "Recherches sponsorisées"

4) Pressing shift + tab goes on one of the skipped button

Best regards,
Alex.