15. The non-transitory computer readable medium of claim 14 , wherein the operations further comprise, in response to entering the new tag in the tag input field, displaying a list of existing tags that are similar to the new tag being entered in the tag input field as suggestion to allow the user to select one of the tags from the suggested tags without having to complete typing of the new tag.
14. The non-transitory computer readable medium of claim 13 , wherein the operations further comprise displaying a tag input field within the sidebar window to allow the user to enter a new tag to be associated with the document page displayed in the main window and to be associated with at least one of the listed available communities.