For various reasons and various thresholds, some comments to questions and answers can become hidden.

When this happens, the link below the comments changes from add comment to something like:
add / show 5 more comments.

It does not appear that it is always the case that all hidden comments have no up-votes or that all visible comments have some up-votes.

The first problem:

If after reading through the comments, you see that there are hidden comments, you click the link and the hidden comments are then shown, but you have no way to identify which comments were hidden and are now shown. Then, if you want to read the now unhidden comments, you have to go back to the top of the list and read or scan through everything again.

Second:

If there are only a few comments, you might be able to see that there are hidden comments so you can click to show all comments before you begin to read the comments... but even this is not very intuitive. If there are many comments, the link is not immediately visible, so you can't tell that some comments are hidden until you have already read through at least some of the visible comments.

Proposed new feature:

1. When comments that are hidden are shown by clicking the link, the unhidden comments should be identified in some way. They could be identified by:

• Displaying them inside a full thin border.
• Displaying them with a vertical bar on the left or right.
• Displaying them with a light colored (different colored) background.
• Displaying them with an (small) icon to indicate these were hidden comments.

2. Place the link: show 5 more comments above the list of comments so you are aware there are hidden comments ahead of time, so you can expand the hidden comments (if you wish) before reading them. The link below the list could remain as it is so you could click it to expose the add comment function if you didn't click it from above the list.