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The comments are displayed in the Bug Details area which . The Comments Toolbar provides additional functionality for working with comments.
The comments which are saved locally have the <new comment> tag instead of the comment author label and can be modified or removed. To do that, right-click the comment and select Edit Comment or Delete Comment accordingly.
Once a comment is uploaded to Bugzilla the <new comment> tag is changed to the comment author label and the comment cannot be modified anymore. Instead, the Reply to Comment option becomes available. Right-click the comment to select this option.
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- Arrange comments by creation date. Use the
Oldest First and Newest First 
buttons. - View comments in a thread. Click the Threaded Comments View button
to see the thread structure. - Expand all comments. For the first ten comments the full text is shown. For other comments you can see only a fixed number of symbols and you need to click the comment to see full text. To expand all comments at once, use the Expand All Comments button
.