How do you browse and upload a photo from an iPhoto Library to a website using a browser like Safari, Chrome, Firefox, etc
The iPhoto Library folder can not be browsed directly. In Finder you can open/access it by righ-clicking and selecting the "Show Package Content" option, but this is not possible in the Open dialog.

But there is an easier way: you can access the content of your iPhoto Library directly from the file browser in the Open dialog:



This also gives you all your events, albums etc. to browse through.