Thanks a lot for the explanation, Andras.
I have uninstalled the extensions.
However, I believe this is clearly a programming / development issue.
The Contents list in the Help pages should finalize with a localized
item such as "Extensions extra help pages" so that the users would
know the next subitems would refer to an extension.
That is something that would clearly improve the intuitive character in Help.
Some developer should address this issue.
Users like me are not supposed to know automatically that such help
pages refer to an extension, but if they are preceded by some short
explanation such as "Extensions extra help pages", then we would know.
Thanks to all you folks.
regards
Carlos