In Bitbucket there are two places that you can add comments. You can go to the commit page, find the file and line that you want to add a comment to and you are able to successfully add a comment. You can also view the code (on the Diff) tab of a pull request and you can add comments and tasks there.

The issue is, comments added from the commit view do not always show up when you view the code from within a PR and vice versa. There are a few ways that this could be better.

1. Display both Commit and PR comments regardless of where you are looking at the code. Different comment types could be displayed in different colors to know where they were added from
2. Put some type of indicator on the screen to let the developer/reviewer know that there is a commit comment when viewing from within a PR or a PR comment when viewing from within a commit
3. Put some type of indicator on the screen to let you know what mode you are in when viewing the code (either Commit or PR, the heading was not apparent).

The problem comes mostly for inexperienced developers or reviewers who don't understand the difference between pull request comments and PR comments. In my testing, I found it that commit comments inconsistently were added to a PR and sometimes I was able to add a task to a commit comment (usually the first time I added a comment I could add a task but subsequent comments did not allow a task to be assigned) I was never able to see a comment or task that was added to a PR when viewing the commit directly. You should also be able to view and resolve tasks when viewing code from the commit view but this may be a separate issue.