Thanks to Cr@@gle for this helpful information, I'm posting this for other users if they happen to run into same problem as I have. In order to get the Community Gallery: Image Author Comment Icon plugin displaying in Gallery + Gallery Extension, just make the following changes in template file: __imageAuthorComment
Change first line:
Code
{if $__gallery->isActiveApplication() && $templateName == 'image' && $image->userID && $image->enableComments}
to
Code
{if $__gallery->isActiveApplication() && ($templateName == 'image' || $templateName == 'imageExtended') && $image->userID && $image->enableComments}
Done.
It now displays the author comment icon in gallery extension. Also, this plugin is compatible with 4.1.1.