When comments are placed on a proof created from a URL link, when it comes time to check whether those to-dos were actioned, you can view the comment and its screenshot and then switch to view the live URL, right from inside of PageProof.
To check whether the comment was actioned
Select the comment to reveal the screenshot that was taken when the comment was placed. The screenshot will show the pin/line/area markup that the comment refers to.
Click the 3 dots icon found on the upper right corner of the comment to reveal the metadata about the comment (device size, browser, scroll position, and page).
Click the restore web page view icon to switch to the correct view and position on the live URL to check if the change request was made.