Loads a preview of top-level comments (such as translations) and lets you comment on the tag
Check the first 20 top-level comments in a little popup dialog, by clicking the "Comments" button.
Add a new comment to that tag, and edit your own comments from within the dialog.
Load comments for all tags on the page at once with the "Load All Comments" button.

Go into your bins:
If one of the existing comments was posted by you, you'll see an Edit button next to your name. Clicking it will load the comment text into the textbox and you can update it.
You can also choose to check all tags on the page for comments at once:
"Comments" buttons are there by default, but if you use Action Buttons Everywhere to specify which buttons to show, and didn't select (hid) the "Comments" button, this script will force-add it back.
You should disable or delete the 'Comment on tags without leaving the bins' and 'Check for Comments from bins' scripts, because they do the same thing.
If you have the latest version of the Comment Formatting and Preview script installed, you'll get the formatting buttons above the textbox.
You can only see top-level comments—not whether they have replies, and you can't reply to them from within this dialog.
A note on rate limits vs. memory usage: Each tag's comments are cached in your browser, and it's only emptied when you close the tab.
This script was inspired by the Comment on tags without leaving the bins and Check for Comments from bins scripts. It expands on those ideas, but doesn't share any code in common.